The Psychology of Cheating: Why People Are Unfaithful

If you’ve ever been cheated on, you’ll know how disorienting it can be – you’re angry, heartbroken, and confused all at the same time. How can someone cheat on the person they love, and why do they do it?

What “counts” as cheating is defined by your relationship. Sometimes, we simply aren’t on the same page about boundaries. However, some people still cross boundaries in relationships even when they’re clear and agreed upon.

In this article, we’ll explore the psychological research behind why people cheat, what cheating might look like, and how to heal after being cheated on.

What Counts as Cheating?

It’s fairly common to feel betrayed by something your partner doesn’t see as cheating. We don’t often feel like it’s necessary to explain where our boundaries are, tending to assume that what is and isn’t okay when in a relationship is implied or universally understood.

However, we actually have very different assumptions about what counts as cheating. This can lead partners to hurt each other while genuinely believing they were doing nothing wrong. As an example, one study found that what we consider cheating varies significantly depending on attachment styles¹. In short, people with high attachment anxiety considered more behaviors to be indicative of cheating than people with high attachment avoidance – see our article on micro-cheating for a deeper discussion on this study.

It’s best to discuss boundaries with your partner so that there’s no need for anyone to assume, but since cheating usually involves hiding things from you to avoid consequences, this in itself could be considered a betrayal.

What Are the Different Types of Cheating in a Relationship?

Since cheating is defined by mutual understanding in your unique relationship, some of the examples given might not constitute cheating for you and/or your partner. However, these are common examples of different types of cheating in a relationship.

Physical (sexual) infidelity

Physical cheating is what we most commonly think of when we think of cheating – kissing, sexual contact, or any overly familiar touching might cross a boundary. While this type of cheating might be the most obvious, smaller physical actions like hugging or greeting people with a kiss can sometimes cause disagreement.

Emotional infidelity

Emotional cheating can be more difficult to define and agree on. Building deep intimacy with others and confiding in another person can sometimes be thought of as emotional infidelity, but some people might think of these as signs of a good friendship.

Digital / online infidelity

Digital cheating can range from using dating apps – this usually crosses a line even if you don’t intend to meet with anyone – to sexting, parasocial relationships with people who post sexual content, or even forming sexual and romantic relationships with AI chatbots.

Micro-cheating

Micro-cheating can be the most difficult to define. It involves crossing boundaries very subtly, which may gradually build up to full-on cheating. Read our full-length article on micro-cheating for more.

Financial and other gray-area betrayals

If your partner has been sending money to, or paying for things for, another person without being honest about it, this could be considered cheating too – even if there was no emotional or physical cheating involved. Lots of betrayals involving another person can be thought of as cheating.

Ultimately, your feelings about a betrayal and dishonesty are valid whether you label it as cheating or not. People who have been cheated on are often just as upset, or even more so, because their partner lied and hid things from them as they are about the actual event.

Why People Cheat: The Bigger Picture

More than a fifth – 21.5% – of people in monogamous relationships have physically cheated, according to a 2011 study of almost 1,000 Americans². Those who had cheated were more likely to report low relationship satisfaction, although the direction of this relationship wasn’t explored – were people more likely to cheat because they were unhappy in their relationship, or were they unhappy in their relationship because they were hiding things from their partner?

In a review of existing studies, Polish researchers explored the causes and impacts of physical, emotional, and online cheating³. They discussed several studies which found that people who had discovered they’d been betrayed experienced severe mental health symptoms, including thoughts of harming themselves. 87% of people who were cheated on blamed themselves – but there are lots of reasons people cheat, and not all of them are within the betrayed partner’s realm of control.

Reasons people cheat can be categorized in 2 different ways: dispositional reasons, which are pre-existing factors that might make someone more likely to cheat, and situational reasons, which are short-term situations that might lead to cheating.

5 Dispositional Reasons People Cheat

According to the Polish review, 5 dispositional reasons people cheat are³:

1. Demographics – Men are usually thought of as more likely to cheat, but the “gender gap” in infidelity seems to be closing. People who are less religious, higher educated, and make more money are also more likely to cheat, probably due to their lifestyles providing more opportunities.
2. Personality – Neuroticism, difficulty forming attachments, and an open attitude to sex are associated with higher likelihood of cheating.
3. Relationship Quality – Low relationship satisfaction has a strong association with the likelihood of cheating.
4. Relationship Set-Up – If one partner works outside the home while the other does not – either because they work at home or they don’t work – there might be more opportunities to cheat.
5. The Internet – The researchers note that the internet makes cheating much more accessible, with approximately one third of Internet users using it for sexual purposes.

8 Situational Reasons People Cheat

Situational reasons for cheating are more short-term in that they can be quicker to happen and quicker to fix than dispositional factors. Checking off everything on these lists doesn’t necessarily mean someone will definitely cheat, but situational factors on top of dispositional factors can increase the likelihood of cheating.

An American study published in 2021 listed 8 situational factors that were associated with cheating⁴:

1. Feeling angry at something your partner has done.
2. Feeling your partner doesn’t meet your sexual needs.
3. Feeling a lack of love and intimacy from your partner.
4. Low emotional commitment in the relationship.
5. Need for more autonomy.
6. Difficulty understanding the situation.
7. Feeling neglected or mistreated by your partner.
8. The desire to have multiple simultaneous sexual partners.

How Attachment Style Drives Infidelity

It would be easy to blame one attachment style over another when it comes to cheating, but the evidence shows that the influence of attachment on cheating is actually quite complex. Studies have not been able to agree on which attachment styles are more likely to cheat, and your partner’s attachment style influences your own likelihood of cheating – although they do tend to find that attachment insecurity in general, in either partner, is associated with infidelity⁵, ⁶.

With that said, there are some interesting interactions between attachment style and other factors that are worth considering. It could be that your attachment style alone isn’t enough to influence cheating, but its co-occurrence with another factor might be.

For example, one study found that attachment anxiety was associated with infidelity behaviors on its own, but the effect was even stronger when they also had a fear of being single⁷.

In another study, people with fearful-avoidant or anxious-preoccupied attachment styles (both high in anxiety) were more likely to cite intimacy and self-esteem related reasons for cheating, e.g. they weren’t getting enough intimacy from their partner⁸. On the other hand, people with the dismissive-avoidant attachment style were more likely to cheat for autonomy-related reasons, such as needing to feel like they had more freedom.

Attachment anxiety and attachment avoidance therefore seem to influence cheating through different mechanisms. We can’t say definitively that any insecure attachment style is more likely to cheat than another, but it does seem that attachment security in a relationship is less associated with cheating. This could be because a secure attachment promotes open communication and an ability to resolve feelings of anger, neglect, or a need for autonomy together.

What Happens When You’ve Been Cheated On?

Your emotional response to being cheated on can be intense, scary, and sometimes confusing. It isn’t always what you expect it to be, or even what you might want it to be.

Being betrayed in a relationship can feel a lot like abandonment, even if your partner wants to stay and fix it. This abandonment is triggering for insecure attachment styles, so you might find your attachment responses heading into overdrive.

If you tend toward attachment avoidance, you might feel an intense need to be separate from your partner and experience avoidant shutdown during interactions with them. Since you likely have good self-esteem but low trust in others, you might direct blame and anger toward your partner.

If you tend toward attachment anxiety, you might feel an overwhelming need to be close to your partner, even if you’re upset with them. Your lower self-view but positive assumptions about others can lead you to blame yourself and direct anger and guilt inward. This response can be particularly confusing.

Your Attachment is Fluid; Attachment Security Can Be a Rock

You might also experience both attachment responses at different times, in line with a typical fearful-avoidant response. Remember that your attachment style can change, and a significant relational experience like this could influence changes to your attachment style – this is why you might not react the way you expect to.

If you have a secure attachment style, being betrayed is still a very distressing event. It’s normal to have an intense emotional reaction including symptoms of depression and anxiety², even if you have a strong sense of self and support from others.

You can also still experience attachment anxiety and attachment avoidance in response to being cheated on, even if your attachment style is generally secure. However, if you have a good baseline of attachment security and secure attachments with others, you might find it easier to move on and heal after being cheated on.

Healing After Infidelity and Moving Toward Secure Attachment

Whether you’re the partner who cheated or the partner who’s been cheated on – or, indeed, both of you are on both sides – healing and repairing your relationship takes time and effort. Understanding both of your attachment styles and the attachment dynamics within your relationship can empower you to name and recognize the mechanisms behind what happened, and what’s happening for you now.

These conversations are uncomfortable, but it’s important to discuss any unmet needs in your relationship so that you can both understand what happened and how to avoid the situation that led to it. Emotional regulation skills are important to be able to manage these difficult conversations.

Your attachment styles and attachment dynamics might change in response to this event, and that’s okay. You can still rebuild attachment security by demonstrating that you trust your partner, and that your partner can trust you. This requires both boundaries and an ability to sit with discomfort.

Boundaries and Discomfort While Rebuilding After Cheating

Trusting someone who’s betrayed you can be very difficult and very uncomfortable, so it can be tempting to ask for reassurance in the form of evidence or control. However, these are not healthy behaviors and can actually lead to a decrease in trust for both of you. For example, you might ask your partner to send you a video to prove they’re alone or with who they say they are, or allow you to search their phone.

When your partner does these things for you, it can temporarily relieve the anxiety, but this doesn’t effectively help you to manage the anxiety or build trust again. It’s like putting a band-aid over a broken bone: it might look like it’s better, but nothing’s healed. Further, because you’re conditioning your brain to find quick relief, you’re strengthening the brain pathways associated with the feeling of anxiety which leads to it coming on quicker and stronger next time.

These strategies can also make your partner feel controlled, diminishing their trust in you as you’re not allowing them to make their own choices. It’s understandable that you might not trust their decisions, but letting them make their own choices now is the only way you’ll be able to trust them to make the right ones in the future.

Boundaries are not for control. Instead, consider them as boundaries for yourself: communicate your needs, understand what you need to do if your needs aren’t met, and stick to the plan. For example, if you need your partner to make more effort to show that they care for you, tell them how you want them to do that and what you’ll do if they don’t. This might be spending time with people who do make you feel cared for instead of with your partner, or reconsidering the relationship.

It’s important to consider that attachment security also requires trust in yourself. If you feel like staying with your partner betrays your own needs, or you can’t trust in them or yourself right now, it might be time to end the relationship so that you can focus on yourself.

Conclusion

It can be difficult to understand why someone would cheat when they’re in a committed, loving relationship, and the reality is that there’s no simple answer. People cheat for a number of reasons, and some of them are easier to manage and avoid than others.

Having an insecure attachment style can influence your likelihood of cheating, but the reasons vary. High attachment anxiety can lead someone to cheat out of a need for closeness, while high attachment avoidance can lead someone to cheat out of a need for autonomy. Whatever your relationship dynamic, unmet needs are usually involved in infidelity.

Your attachment style can also affect, and be affected by, what it’s like to be cheated on. Your attachment style can change, and it’s likely to be affected by a significant betrayal like this, so it can be helpful to re-evaluate your attachment dynamics often while healing from any type of cheating.

To find out your attachment style, take our free attachment quiz – and don’t forget to save your results and come back another time to see how things might have changed.

FAQs

Which attachment style cheats the most?

Research finds that insecure attachment styles are typically more likely to cheat, but there is no consensus on which one specifically. Both attachment avoidance and attachment anxiety are associated with cheating for different reasons.

Can a cheater change?

It’s possible for people who cheat to change their relationship habits and earn more attachment security, but it takes time and effort, and they have to want to change.

Is emotional cheating worse than physical?

There are several different types of cheating, and all of them can lead you to feel betrayed and abandoned. Which type of cheating you experience the most intensely depends on your own personal values.

Do cheaters ever stop cheating?

People who cheat habitually might have strong dispositional factors related to cheating. It’s possible for them to stop cheating, but this depends on their own unique motivations and effort.

What does psychology say about infidelity?

Psychology says that people cheat for a number of different reasons, usually relating to unmet needs in the relationship.

References

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