Why Do People Cheat When Open Relationships Are an Option?

Cosmopolitan

18-07-2025

Thanks to a recent incident involving a certain concert, a rumored workplace affair, and brief moment of Jumbotron PDA (IYKYK), I, like many people, have been thinking a lot about cheating lately. Not on my own partner—I don't have one (DMs are open, boys), although I did think about cheating on the one that I had when I had him.
Maybe that's part of the reason why I find it so surprising that public cheating scandals are even still a thing in our presumably progressive, sexually enlightened era. In an age of seemingly mainstream polyamory, how is cheating really still such scandal fodder? How is it still so shocking that people's sexual desires—and behaviors—don't always fit neatly within prescriptive social norms?
On the other hand, it makes sense that all our sexual enlightenment may have only further soured attitudes toward infidelity. After all, in a time when various forms of ethical non-monogamy seem to be an increasingly accessible and acceptable option, why cheat when you can just have an open relationship?
It's a good question, for sure. Why risk hurting someone you love—not to mention potentially blowing up your own life—when you could have a consensually non-monogamous relationship in which everyone gets what they want and no one gets hurt? All's fair in love and non-monogamy, right? As open relationships and other forms of non-monogamy increase in visibility and popularity, it makes sense that cheating would seem all the more tawdry and dated.
It's sound logic, don't get me wrong. But there are a few issues with this assumption that ethical non-monogamy can be expected to function as some kind of modern antidote to infidelity. Let's unpack, shall we?
Unfortunately, cheating is something that can happen in any relationship, however open it may be.
Just like traditional relationships, non-monogamous partnerships function around a 'monogamy agreement,' or a set of expectations and boundaries each partner is expected to uphold. Any violation of that agreement could be considered cheating, says Tammy Nelson, PhD, author of Open Monogamy and When You're the One Who Cheats.
Unlike monogamous partnerships, in which the whole 'We're not supposed to have sex with other people' thing is pretty universal, monogamy agreements and what it means to violate them may look very different from open relationship to open relationship. And even within those relationships, expectations may not be exactly the same for each partner. For example, one person might want to know when their partner has sex with someone else, while the other would rather be spared the details.
'Sometimes cheating in an open relationship can be as simple as going out for coffee with a new partner that is off limits, or an ex, or someone outside of the 'pod,'' says Nelson, adding that more partners can often create more complex dynamics. 'It can be complicated to get 'approval' from multiple partners if you are in a group relationship, and some people find it easier to break away and do what they want on their own.'
Regardless, whether you're breaking a closed monogamy agreement or an open one, 'cheating is cheating,' says sex therapist Jamie Schenk DeWitt. 'The cheater, by definition, is not playing by the rules that have been established and agreed upon.'
It may seem like everyone is opening up these days, but while non-monogamy is definitely becoming more mainstream, it's a long way from being the norm.
'Many folks don't want open relationships,' says Zachary Zane, author of Boyslut: A Memoir and Manifesto and a sex and relationships expert for Grindr. 'If your partner doesn't want one and you still want to be with them, then you're going to have to lie about having sex with others.' That doesn't excuse cheating, to be clear, but it does explain why it still happens in our seemingly sexually evolved timeline.
Not to mention, the idea that you can just seamlessly convert a monogamous relationship into an open one to spare yourself the burden of infidelity is kind of a massive oversimplification of non-monogamous partnerships and the work that actually goes into maintaining them. Not everyone is cut out for that work, and some people simply don't want to do it.
'Open relationships take work,' says Zane. 'For many, it's just easier to cheat and lie about it.'
Perhaps unsurprisingly, cheating in open relationships tends to happen for more or less the same reasons as good old-fashioned adultery. Your monogamy agreement—whatever it entails—isn't working for you anymore, and cheating seems easier than talking about it. Or maybe you know that whatever it is you want to do would be a hard no for your partner(s), so cheating feels like the only way to satisfy those desires without threatening your relationship.
'One thing that many cheaters have in common is that they don't want to confront issues or feelings that may be impacting the connection and health of their current partnership,' says DeWitt. 'They would rather avoid confrontation with their partner to get their needs met.'
So we cheat, whether on one person or several, in a closed relationship or an open one. We cheat out of convenience or laziness or selfishness or any combination of factors.
It may seem like open relationships are the key to finally being able to have our cake and eat it too, to cheat without cheating, to Have It All.
But the reality is that open relationships are a compromise, just like anything else. For some, non-monogamy may be a way of reconciling otherwise conflicting desires, but not without its own complications. This is not to say that cheating is a better or even defensible option. But even as someone who now identifies as non-monogamous, I'd argue that the idea of using open relationships to avoid infidelity is one that oversimplifies non-monogamy and ignores some key, if uncomfortable, realities of human desire and behavior.
'I think there will always be cheaters,' says Sheff. 'I think it will lessen as people come to know ethical non-monogamy as an option. But the 'I want multiple partners and I don't want you to have them,' I think that's a permanent feature of the human psyche.'