Dating & Relationships

Inside an Affair: What People Do, Say, and Feel When They Commit Infidelity

January 18, 2021 by Justin Lehmiller

There’s a lot of research out there on infidelity. Most of it has examined topics such as how many people have ever cheated and the main reasons people step out on their partners. However, we don’t actually know all that much about what actually happens during an affair itself. Specifically, what do people do and say, and how do they feel about it?

A new study published in the Journal of Sex & Marital Therapy offers some revealing insight into the actual dynamics of an affair, and how those dynamics differ based on people’s motivations for cheating in the first place.

In this study, researchers examined the infidelity experiences of 495 young adults (average age of 20, 88% of whom identified as heterosexual). In an online survey, participants were asked to describe an instance of infidelity in either a current or past relationship, which included reporting on the sexual and intimate behaviors that took place, how satisfied they were with the encounter(s), how long they carried out the affair, and more. Here’s what they found:

How Long Do Affairs Usually Last?

Affairs can be short- or long-term. In fact, participants reported affairs lasting anywhere from less than one day to over 5 years, with the average length being about two months and the median (50th percentile) length being about two weeks. However, it’s worth noting that women reported having longer affairs on average than men: 75 days vs. 53 days, respectively.

Longer affairs were also linked to cheating due to a lack of love in the primary relationship, seeking to boost one’s self-esteem, and desiring more sexual variety.

Which Sexual Behaviors Occur in an Affair? 

In terms of the behaviors participants reported engaging in with their affair partners:

· 87% reported kissing,

· 73% reported cuddling or close touch,

· 54% reported mutual masturbation,

· 53% reported vaginal intercourse,

· 46-47% reported giving or receiving oral sex,

· 6% reported anal intercourse

· 6% reported that their affair was not physical or sexual in nature.

It’s notable that, in a sample of predominately heterosexual persons, only about half of affairs involved vaginal intercourse and that the most common behaviors were kissing and intimate touch. This points to something we’ve long known about affairs, which is that many of them are not really driven by unmet sexual needs, but rather unmet needs for intimacy and emotional connection.

In terms of sexual satisfaction, men were more likely than women to say that the sex they had with their affair partner was better than sex with their primary partner; however, men and women did not differ in their reports of how sexually satisfied they were with their affair.

Those who were more sexually satisfied with their affair had affairs of longer duration and were more likely to be cheating due to lack of love, desire for sexual variety, and because there was a desire discrepancy in their primary relationship (e.g., their partner lost interest in sex).

Lack of love was also linked to people taking their affair partners on more public dates and engaging in more public displays of affection with them.

What Do People Say During an Affair?

Given that sex is often (but not always!) a big part of affairs, it’s not surprising that 61% of participants reported having sexually explicit dialogue with their affair partners. However, even more (63%) reported expressing fondness and affection, and many (38%) reported engaging in intimate conversations.

Also, just over 1 in 10 participants said “I love you” to their affair partner. Those who exchanged these words tended to have longer affairs and were the most emotionally satisfied with them.

Men and women did not differ in rates of sharing intimate dialogue, nor in terms of how emotionally satisfied they were with their affair. However, men were more likely to report sexually explicit dialogue with their affair partner than women.

It’s important to note that these findings come from a study of young adults—people who likely have not been in any relationship for very long and who do not have an extensive romantic history in general. Thus, it is quite possible that the affair trajectories of older adults might be a bit different.

That said, these findings tell us that there seems to be a lot of diversity and variability in the dynamics of an affair in terms of what people say and do—and how they feel about it. This is important to understand for several reasons. Infidelity is one of the biggest causes of relationship conflict and divorce, which can have detrimental effects not just on the partners themselves, but also on any children they might have. By better understanding infidelity—including the underlying motivations, outcomes, and typologies—this can potentially help sex and relationship therapists to better assist clients who may be struggling with this.

So what happens after an affair? How often do people tell their primary partners about it, and how does it affect their relationship? And what happens with the affair partner—do people cut off all contact, remain friends, or start committed relationships with them? Stay tuned because I’ll be answering these questions later in the week with more findings from this study.

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To learn more about this research, see: Selterman, D., Garcia, J. R., & Tsapelas, I. (2020). What Do People Do, Say, and Feel When They Have Affairs? Associations between Extradyadic Infidelity Motives with Behavioral, Emotional, and Sexual Outcomes. Journal of Sex & Marital Therapy.

Image Source: 123RF/Ion Chiosea

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Written by
Dr. Justin Lehmiller
Founder & Owner of Sex and Psychology

Dr. Justin Lehmiller is a social psychologist and Research Fellow at The Kinsey Institute. He runs the Sex and Psychology blog and podcast and is author of the popular book Tell Me What You Want. Dr. Lehmiller is an award-winning educator, and a prolific researcher who has published more than 50 academic works.

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