Infidelity: Why people cheat, and what to do if it happens

8 min

Infidelity can be one of the most emotional, damaging and difficult situations a couple will ever face.

Also known as cheating, infidelity — commonly defined as being unfaithful in a married or committed relationship — can take many forms. It might be a long-term affair or a brief sexual ‘fling’. It could be emotional infidelity, or inappropriate physical contact. It could even happen entirely online.

Most people expect a romantic partner to be trustworthy and provide them with security, so it’s not surprising infidelity can fracture or even break a relationship. 

So, how common is infidelity? Why do people cheat? Can couples recover from it? And how should someone, whether they have cheated on their partner or been cheated on, get through it? 

How common is infidelity?

Exact numbers are impossible to settle on but one study estimated that in Western countries, between 25 to 50% of divorcees said their spouse’s infidelity was the main cause of the divorce. However, given the negative connotations of words like infidelity and cheating, it is likely the behaviours are under-reported.

Elisabeth Shaw, CEO of Relationships Australia NSW, says in her experience, infidelity is reasonably common, although its definition differed from person to person.

“This is a very common issue in relationships, but how people define it can be quite mixed,” she says. “Once upon a time it (infidelity) would have been (defined as) a physical affair which was sexually based. There’s been a lot of developments, particularly in the online environment, around emotional affairs, such as online sex. Some partners can see that as being unfaithful, and some people also see regular use of pornography as a version of infidelity. 

“The key thing is, these actions take energy — sexual, romantic or emotional — away from the primary relationship. 

“So, infidelity can be experienced in a nuanced way. (No matter how it happens), the other partner will feel it as a threat — a threat to the relationship.” 

The good news is, some couples can recover from the heartbreak of infidelity.

“A lot of couples can get past it. It can be hard to recover from but in fact many couples even feel stronger after the work they put in — not stronger because there’s been an affair but stronger because they work on it and work out what it was all about,” she says. 

Why do people cheat?

There are no definitive reasons for why some people cheat, although a survey of 5,000 people in the UK found some differences between the reasons men and women are unfaithful. 

For men, the top five reasons were a lack of communication between partners (68%), stress (63%), sexual dysfunction with one’s current partner (44%), lack of emotional intimacy (38%) and fatigue or being chronically tired (31%). For women, the leading reasons were lack of emotional intimacy (84%), lack of communication between partners (75%), tiredness (32%), a bad history with sex or abuse (26%), and a lack of interest in sex with the current partner (23%).

What to do if you suspect infidelity

This is an area where communication between a couple is vital. Relationships Australia NSW states that if a “whole lot of things don’t add up and you suspect infidelity, then speak up. You don’t have to be correct, but you do need reassurance that your concerns are taken seriously and worth responding to. 

“If your partner can’t provide this, it’s not necessarily confirmation of their infidelity, but it could still raise other concerns about their reliability and the level of emotional support they’re capable of providing.”

Shaw says trying to ensure the conversation doesn’t become overly emotional is important.

“The first thing to do is raise it (your concerns) — not as an accusation though,” she says. “It’s better to use (language) about ‘we’, as in ‘I’m worried that we’re not as close as we were,’ or ‘we’re not spending as much time together’. If you just blurt out ‘are you having an affair?’ then it often makes the other person defensive.”

What should you do if you cheat on your partner?

There is no failsafe plan to follow if you have cheated on your partner. You’re probably going to cause significant pain but you need to work out whether the affair was a sign the relationship was on thin ice, or whether you want to find a way to save the relationship.

Shaw says if you want to save the relationship, then it’s vital to be truthful to prevent the situation becoming even more damaging.

“If you’re accused of doing it and you have been, it’s better to be honest because if you deny it, you get into a whole web of trouble,” she says. “The issue is lack of trust — you haven’t been trustworthy in the relationship, so if you then tell further lies and denials, it will eventually come out, and you continue to look untrustworthy. 

“You can start to rebuild trust right from the beginning by being accountable and honest. Trust has to be earnt … the process of owning up to it and being accountable is important.”

People who want to rebuild their relationship must also be truthful with themselves, Shaw says.

“If you put blame on the other partner, it’s not useful at all. It’s an easy thing to say ‘the relationship must’ve been the problem’ but individuals are responsible for their actions, even if the relationship is in trouble,” she says. “It’s better to own the issue than to continue to lie.”

What to do if you’ve been cheated on

Unfortunately, there’s generally no easy way to deal with being cheated on. You’re likely to experience a vast array of difficult and hurtful emotions, but Shaw says there are some things that can help you through the ordeal.

“The important thing is, even though it is hard to believe, they should try not to take it personally,”

– Elisabeth Shaw

she says. “Because the person who had the affair, it was their choice — you may feel that there’s things you could have done differently, but even if you can fix those things up, you’re not to blame for what has happened because it wasn’t in your control.”

Shaw added the person who was cheated on needed support to deal with the situation, but her advice was for them to avoid telling too many people about what had happened.

“You do need to get your own support, but … it’s better not to tell too many friends and family because later, you may repair things and go on and have a successful relationship, but if your friends and family have taken sides and are really angry out of loyalty and they are they are backing one party or another, that can be really messy,” she says. “It can undermine things. 

“Maybe choose one trustworthy friend to talk to, and then see an individual counsellor to think it through in a private space where you are safe. Then, if you do want to work on the relationship, find a well-qualified couples counsellor who is experienced in infidelity who can help you.

“Often (during counselling), couples do look at areas of their relationship that have become weaker — not because it’s the reason the affair happened, but they can learn a deeper understanding of the context of their relationship. In shoring up their relationship to be strong and connected, they can almost start future-proofing their relationship so hopefully it won’t happen again.”



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