Why having 'couple friends' is good for your marriage

I was watching Thirtysomething the other day with my fiancée. It started off as a joke while scanning Netflix – oh my God, Thirtysomething! – but then we got hooked. As kids, we both watched the prime-time soap over our parents' shoulders, understanding very little of what was happening.

Now, however, 25 years after the show first aired, we're pretty much living it: in our 30s, surrounded by pregnant couples, couples with small children, and single friends looking to pair up. I never thought it would happen – I'm one of them.

One of the most revolutionary things about the show was its portrayal of life beyond the nuclear core that we saw in Family Ties or The Cosby Show. Even as couples with kids, it seemed to say, we're part of an ensemble cast.

It's a message that has even more resonance today, according to a new book that looks to be mapping out the future of my social life – Two Plus Two: Couples and Their Couple Friendships. Authors Geoffrey Greif and Kathleen Deal – both professors at the University of Maryland School of Social Work – argue that there are benefits to filling one's social calendar with foursomes.

Couple friends, they say, introduce novelty into our lives, suggest activities we wouldn't do on our own and, most interestingly, act as a mirror. Couple friendship "provides a cross-check on one's own marriage by offering a lens on the inner workings of another intimate relationship," they write. They even go so far as to say that the dynamic that other couples add to a marriage is one of the keys to making it last.

They note that in the past, the job of maintaining a couple's social circle would almost always fall to the woman. It would seem to follow that now, when many women focus on their careers or start businesses like the two male leads in Thirtysomething, guys will have to step up and play social organizer, too.

Luckily, my generation has already primed itself for this shift. We grew up with what I'd call the St. Elmo's Fire social paradigm – guys and girls going out in co-ed, half-platonic, half incestuous clusters. In fact, my best friend's parents used to make fun of us for "hanging out in groups," because in their day, they only fraternized across the gender divide on formal dates.

"Men and women are more apt to be friends than ever before," Dr. Greif agreed when I spoke to him on the phone. "When our fathers went to work, women were not peers. Now, they work alongside men. If I'm used to treating a woman at work as my peer, that opens up my possibility of considering her a friend."

Double dates are more fulfilling, Dr. Greif explains, if all four members click. There's no doubt that this is more possible now that cross-sex friendships are commonplace. For many of the St. Elmo's thirtysomethings, socializing isn't expected to divide along gender lines. It may naturally still do that, but where there's still that expectation, it rankles.

"I resent the idea of getting together as a foursome or more and it being suggested that I have something in common with the women by nature of our woman-ness," my friend Andrea complained. "With some couples, there's a suggestion that you are automatically supposed to relate to the women, and do things like make fun of the guys, which I find disrespectful and unsexy. Or you're supposed to talk about whatever women are supposed to talk about, like domestic stuff and life plans."

I wondered if the habit of making friends with the opposite sex in our youth could allay one of the things even Dr. Greif had to admit can go wrong with couple friendships – affairs.

"There can be sexual tension between folks," he said, explaining that as he interviewed hundreds of couples for the book, he came across more than one cautionary tale. "There was an instance of somebody who was planning his wife's 45th birthday with the wife's best friend and the two of them began having an affair. Planning for the wife became an opportunity for them to see each other alone, which would not have been there otherwise."

In the pilot of Thirtysomething, infidelity is broached between the two male leads when Eliot tells Michael that he's slept with other women. Later, Michael ends up having Eliot's confession dragged out of him by his own wife, but to a positive end; exactly as the authors of Two Plus Two describe, the couple uses their friends' situation as a mirror to talk openly about their own fears of betrayal.

I'm too superstitious to promise that equality of the sexes will ever end extra-marital affairs altogether – obviously, it will not – but I do believe that as we settle in, my St. Elmo's generation will be able to navigate the sexual tension of group friendships much more comfortably than our parents did. This may, in fact, be a key to strengthening the entire institution of marriage, even if it does make for less interesting television.

Micah Toub's memoir, Growing Up Jung , is out in paperback.