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The general thinking about why people cheat on a committed relationship partner is that there is a problem with either the cheater or the relationship. Often, we assume that cheaters have a pathology, some unresolved or dysfunction, or at best a form of emotional immaturity, that pushes them into . Other times, we assume that the primary relationship is flawed in some significant way that creates a perceived need for external and . Either way, we tend to view infidelity as symptomatic of underlying problems. The cheater and/or the relationship is troubled, and cheating is the result.

And guess what, more often than not, this is the case. Sometimes the cheater has an deficit disorder. Sometimes the cheater has unresolved trauma and uses the excitement of illicit sex and romance as a distraction from painful feelings. Sometimes the cheater knows that he or she is in a lousy relationship and uses those feelings to justify the infidelity or to locate a new partner before abandoning the old one. Sometimes the primary relationship lacks sexual fire or emotional intimacy, so the cheater has a one-night stand or an affair to fill the void. And so it goes.

That said, the cause-and-effect model described above doesn’t fully explain all infidelity. Over the years, I’ve had countless clients tell me that they love their spouse, they have a great relationship, they enjoy each other’s company, they respect each other, they’re attracted to each other, the sex is good, and there are no money or family or other obvious relationship problems. The only real issue is that they’re cheating, and they can’t, or don’t, want to stop.

So there the cheater sits, happy in his or her relationship, but still cheating and wondering why. “Surely,” the cheater says, “there must be something wrong with me or with my relationship, or I wouldn’t be doing this.” And typically, a therapist will start to explore those possibilities with them, searching for an obvious underlying problem to explore and address.

What I have learned over the course of nearly three decades as a therapist specializing in sex and intimacy issues is that infidelity is often a symptom of a flawed or relationship, but not always. Some people are reasonably emotionally healthy and in a wonderful primary relationship, and they still choose to cheat. And this is true for both men and women.

Esther Perel, who verbalizes this idea in her book The State of Affairs, suggests four reasons why people who are generally well adjusted and happy in their primary relationship might nevertheless engage in infidelity, risking their , their home, their family, their standing in their church or community, and more.

1. Self-Exploration

Searching for a new sense of self is likely the most powerful of these reasons (and it may encompass the other three). About this, Perel writes:

People stray for a multitude of reasons, and every time I think I have heard them all, a new variation emerges. But one theme comes up repeatedly: affairs as a form of self-discovery, a quest for a new (or a lost) . For these seekers, infidelity is less likely to be a symptom of a problem and is more often described as an expansive experience that involves growth, exploration, and transformation.

For these cheaters, infidelity is an exploration of never experienced or long-repressed parts of the self. It is freedom from who they have been and currently are. Interestingly, they usually don’t want to change who they are; they simply want to escape those constraints for a short while — to feel young again, to feel unburdened, to explore and grow and experience life. When these individuals cheat, they’re not looking for another person, they’re looking for themselves (or, at the very least, for a lost or long-ignored aspect of themselves.)

2. The Seductive Nature of Transgression

Sometimes happy people who cheat say they feel like a teenager when they’re sneaking around and having sex or an affair. It’s exciting and forbidden, and they get a kick out of breaking the rules. It’s like a 5-year-old sneaking a cookie that his mother said he couldn’t have. The forbidden cookie just tastes extra sweet.

In his book, The Erotic Mind, Jack Morin discusses this phenomenon from a sexual perspective with his erotic equation: + Obstacles = Excitement. That is the seductive nature of the transgression. Because the cheater is not supposed to have extracurricular sex and romance, he or she wants it even more. For children and teens, pushing limits in this way is a natural exploration of self and the world. As an adult, infidelity can feel like more of the same.

3. The Allure of Lives Not Lived

Here, instead of transgression, it’s missed opportunities that draw cheaters in. They think about the one that got away, or the one that never was, or the life they could have had if only . . . This may cause them to feel limited and fenced in by the life and relationship they’ve chosen — regardless of how much they enjoy that life and relationship. So, they indulge their curiosity. They use extracurricular sex to see who they might have been if they’d opted for a different path. Again, this is a form of self-exploration, where infidelity introduces the individual to the stranger within.

4. Feeling New or Exiled Emotions

Lastly, happy people who cheat may do so to experience new or exiled emotions. Again, this is a form of self-exploration. Men can be especially vulnerable to this, as they are often told, as they grow up, to repress and not express their emotions. Over time, they learn to “cowboy up” and not feel. Unfortunately, in so doing they often stifle joy as well as sorrow, pleasure as well as pain. For these individuals, regardless of , infidelity is more of an emotional release than a sexual release. And once again, these cheaters are exploring their inner self.

Whatever the Reason, Cheating Hurts

Are some reasons for cheating better than others? And does the answer to that question really matter? From the perspective of the betrayed partner, probably not. For the betrayed partner, sexual betrayal hurts the same, no matter the underlying cause, and there is no good reason to do it. From a standpoint, however, the reasons a person cheats do matter. If a person is happy in his or her relationship and cheats as a way of exploring the self, the approach to healing is very different than with a person who cheats as a (misguided) way of addressing personal pathology, unresolved childhood trauma, emotional immaturity, or problems within the relationship.