Charlie Neibergall / AP

Millennials have killed malls, cheese, and bar soap. Their thirst for blood unslaked, they’re now coming for good, old-fashioned cheating.

At least, that’s according to an analysis that the sociologist Nicholas Wolfinger published in 2017 on the Institute for Family Studies website. When asked the survey question “Have you ever had sex with someone other than your husband or wife while you were married?” Americans older than 55 turned out to be more adulterous than people younger than 55. In fact, people born between 1940 and 1959—that is, people currently between 60 and 79 years old—were the ones who reported the highest rates of extramarital sex.

Americans have been asked the infidelity question in every iteration of the General Social Survey, a broad questionnaire about cultural attitudes, since 1991. Wolfinger’s analysis found that in the early 2000s, 18-to-55-year-olds were more likely to have extramarital affairs than older people were. But right around 2004, the lines cross, and younger people became more chaste than their parents:

Wolfinger takes these data to mean that Ashley Madison’s days might be numbered. Today, the hot new thing for married couples, apparently, is having sex (albeit rarely) with each other until they die. “Barring any unforeseen developments,” Wolfinger writes, “we should anticipate a future of more monogamous marriage.”

Whether or not Millennials are doing marriage differently, they’re certainly changing other parts of courtship. Unmarried couples are more likely to cohabit than they were a decade ago, and the once-fringe online-dating scene has become as mainstream as dinner and a movie. Some people engage in polyamory, while others have open relationships, and more people are talking about those arrangements openly. Both marriage and divorce have become more rare since the 1980s. Between it all is an array of “fuckboys,” ghosts, and friends with benefits.

All these factors together complicate Wolfinger’s claim that marriages of the future will be monogamous. Other researchers I spoke with say it’s not possible to know yet whether Millennials are actually going to have more faithful marriages than Boomers. Several pointed out to me that the Institute for Family Studies is a think tank that explicitly promotes marriage and family; its blog, where the analysis was posted, is not a peer-reviewed academic journal.

Wendy Manning, a sociologist at Bowling Green State University, told me there’s no evidence that young adults who are between the ages of 24 and 32 today are more likely to be faithful than the same age group was in 1980. The difference Wolfinger is picking up on, she said, seems to be just that people over 50 are simply older and possibly have been married longer, so they’ve had more opportunities to cheat. We’d have to wait until Millennials get older before determining whether they are, truly, the faithful generation.

There are some limited data to bolster Wolfinger’s point, however. In 2017, Lindsay Labrecque and Mark A. Whisman at the University of Colorado at Boulder found that even though the percentage of Americans who think extramarital sex is “always wrong” significantly declined in the General Social Survey from 2000 to 2016, the survey’s respondents reported a small but statistically significant decline in the lifetime prevalence of extramarital sex in the same time period. That could mean that the people who were eligible to participate in the survey in 2016 but not 2000, including Millennials, are more open to cheating philosophically, but still less likely to do it.

It’s hard to draw firm conclusions about generations, but Wolfinger’s analysis might be pointing to changing behavior among the subset of Millennials who do choose to get married. To get a sense of how married Millennials think about commitment, I reached out to married Millennials and Gen Xers through Twitter to ask those who are convinced they would never cheat on their spouse: Why? Dozens replied via email and direct message. Twitter, obviously, is not a representative sample of the U.S.; its users tend to be more liberal and educated. However, even among this relatively left-leaning group, many people said they knew of very few cheaters in their social circle, and those who did cheat were looked down upon by their friends.

Junie Gray, a woman from Austin, Texas, told me she doubts she could find someone who “understands, supports, and loves” her like her husband does. Because people today wait longer than previous generations to get married, many simply might be selecting the actual right person for them. There’s no need to cheat when your spouse is your best friend, your soulmate, your “everything.” There’s no “one that got away”; you caught him. It just took you until you were 36 to do so.

As the Johns Hopkins University sociologist Andrew Cherlin put it to me, “over the past few decades, marriage has become more selective.” Today, the people most likely to have lasting marriages are those who have gone to college. And college graduates seem “more committed to each other and to the marriage,” Cherlin said. He pointed out that the divorce rate has gone down significantly for college-educated couples, but not for couples in which neither person has a college education.

I heard from a lot of people who prudently dated their partners for several years before getting married, then waited still more years before having children, just in case. There’s less societal browbeating these days to move faster. “There isn’t pressure to be in relationships like there used to be, so people are less likely to settle for a bad partner,” says Skylar Dallmeyer-Drennen, an energy consultant in Washington, D.C. “Why put up with a cheater if no one needs you to be dating?”

This trend is intertwined with what my colleague Kate Julian described as “the sex recession.” Young people today have less sex in general, so it follows that they are likely having less of it extramaritally, too. “We’re living in an astonishingly sexless age,” Wolfinger told me.

Of course, we are also living in the midst of a sexual-harassment crisis. But a number of #MeToo offenses seem to be perpetrated by older men, some of whom blame changing mores for their alleged transgressions. Though there are also stories of young men who don’t know where to draw the line between friendship and romance, experts say that in general, young people tend to be more supportive of gender equality. Cheating, meanwhile, can feel deeply inequitable. Infidelity sometimes gets lumped in with other types of harm against women: Several of the entries on the “shitty media men” list that was circulated a few years ago involved allegations of affairs.

Or maybe it’s something about being Millennial, rather than a married Millennial, that deters two-timing. A few people who responded to my Twitter inquiry suggested that maybe Millennials in general are still young and idealistic. My generation wants jobs with a purpose, and we want relationships that feel purposeful, too. Or, as a Gen X friend of mine speculated, perhaps Millennials are terrified of breaking rules. We’re so preoccupied with getting recommendation letters and maintaining our brands that we would never sully ourselves with something so carnal and impulsive as infidelity. (My friend asked to remain nameless, because he didn’t want to seem like he was justifying adultery.)

In line with this moral-Millennial hypothesis, many young, married people told me it feels less honorable to leave your spouse for someone else. That would imply there was “emotional cheating” going on while the relationship was in progress—another taboo. “You need to spend some time mourning the end of what had become a formative part of your identity,” says Kae Lani Palmisano, a writer and an editor in Philadelphia.

There’s also the usual explanation behind the “Millennials are killing …” trend stories: It’s that Millennials are broke, and they simply can’t afford to buy whatever it is that’s being killed. In this case, some Millennials are still traumatized by the recession and struggling to launch their careers. They can’t afford to buy a house without a second, steady partner. When so much of your life is in flux and unstable, it’s nice to have one person who will definitely be there for you. Why screw it up?

Beyond lingering economic worries, many Millennials and Gen Xers are scarred by their parents’ divorces. The peak in the divorce rate was in 1979, right as the oldest Millennials were being born and younger Gen Xers were reaching their tender grade-school years. Millennials are much more likely to be the children of divorce than their children will be, if current trends continue. “The specter of divorce looms large,” said Manning of Bowling Green State University. “And it seems like it’s a big reason why a lot of young adults want to live with someone first. They want to divorce-proof their marriage.”

For some young people, fidelity is a way of vowing to do better than your own parents did. A few people told me they had been so rattled by their parents’ divorce that they resolved never to do the same thing to their kids. “My parents divorced when I was 2,” says Cole Novak, a pastor in Texas. “My entire life has been marked by the effects of my parents’ divorce. And I never wanted my kids to grow up the way that I did.” When women send him flirtatious texts, Novak says he responds by adding his wife to the thread.

Even as Millennials murder America’s cultural standbys, they continue to be somewhat inscrutable. For now, it does seem as if their marriages, when they do happen, are more faithful than those of their elders, but it’s just too soon to know for sure whether that will continue. In fact, Wolfinger accepts some of the alternative explanations for what’s going on here. “Do people in their fifties and sixties have the most extramarital sex because they’re in midlife and have been married for 20-30 years, or because they came of age at a time that fostered greater sexual exploration?” he writes. “The answer is probably ‘both.’”

In other words, yes, it might simply be the case that people over 55 are getting older, growing uninterested, and applying the looser sexual mores they grew up in to sex lives that have gotten a little stale. “Being married for a long time means a couple of things: Your kids might be out of the house; you might be bored having sex with your partner,” Wolfinger told me.

Or as a Boomer might say, it might just be that Millennials will understand when they’re older.

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