A new book argues that if the institution of marriage is to endure, it must evolve with the times.

There was something hollow about the hubbub last month over the revelation of Maria Shriver and Arnold Schwarzenegger’s split. As one of the weirder new clichés lately to invade the language puts it, we were shocked but not surprised. Nothing is less earthshaking these days than infidelity: According to current statistics, up to 50 percent of men and 40 percent to 45 percent of women cheat. No, the real scandal was not that Schwarzenegger had been unfaithful; his misbehavior had long been public knowledge. It was that, in fathering a child with his mistress, he had been spectacularly, stupidly unfaithful in a way that even a wife apparently accustomed to overlooking infidelity—a wife who had perhaps decided that a 25-year marriage, with four children, could withstand a few dalliances—could not ignore.

With infidelity now seeming less like a deadly plague and more like a relatively mild form of cancer—we all know someone who has suffered from it, even if we haven’t experienced it ourselves—does it still make sense for monogamy to constitute the basis for marriage? Or should couples figure out creative ways to expand the boundaries of their relationships, acknowledging that they might want to continue to be life partners even if one or both needs the occasional night off? This is the argument of Pamela Haag’s new book, Marriage Confidential: The Post-Romantic Age of Workhorse Wives, Royal Children, Undersexed Spouses, and Rebel Couples Who Are Rewriting the Rules, in which “affair-tolerant” couples aren’t a regressive throwback—they’re the benchmark of a new kind of modernity. Its abundance of gimmicky catchphrases aside, this book asks serious questions about whether we have come to expect too much from contemporary marriage: a partner who is simultaneously an emotional and intellectual “soul mate,” a monogamous provider of sexual thrills, and a best friend to see us through our creaky final decades. If marriage has a hard time living up to these burdens—and a divorce rate holding steady at 50 percent suggests just how hard it is—maybe we ought to be thinking about ways to transform it.

Following Stephanie Coontz, who covered much of this ground more soberly in her book Marriage: A History, Haag notes that marriage has undergone a dramatic transformation from the “traditional” partnerships of the nineteenth century, when marriage was “a social institution and an obligation,” to the “romantic” marriages of the twentieth century, when the practice of choosing a partner for reasons of love rather than practicality first became widespread. Now, she argues, we are moving into a “post-romantic age.” People have become far more likely to marry in mid-life, when they already have established careers and friendships; and they are having children much later than their counterparts did 50 years ago. But they continue to organize their marriages around the same assumptions—assumptions that, possibly, no longer work. “The facts, circumstances, and shell of marriage have changed so breathtakingly in the post-liberation era, yet the soul of marriage—its dreams, conscience, ethics, and rules—hasn’t necessarily evolved to keep up,” Haag writes. “Instead we follow viscerally many of the same premises and orthodoxies as our parents, as if marriage is a Procrustean structure to which we must confine ourselves, rather than the other way around.”

The result, Haag argues, is a widespread dissatisfaction with romantic marriage, evident in an epidemic of “low-conflict, low-stress unhappy marriage.” The couples in these marriages are basically cooperative and compatible—they don’t beat each other, abuse drugs or alcohol, or gamble away all their savings—but they are nonetheless plagued by the feeling that their relationship isn’t everything it should be. They haven’t caught up with the times: They’re trying to live out a romantic paradigm in a post-romantic age. Such marriages look stable on the outside, but they’re astonishingly fragile: Haag quotes a study that finds that they account for up to 60 percent of divorces. Unsurprisingly, she includes her own marriage in this group. “Often, in my own case, I really can’t tell if my marriage is woeful or sublime,” she writes. “Maybe I’m just so profoundly content that it feels like unhappiness, because nirvana is dull in this way, it lacks frisson.”

This is stated oddly—really, shouldn’t there be a bit more separation between woeful and sublime?—but it gets at a real question about what marriage is, or, more exactly, what it ought to be. “Is a partially unfulfilling but stable marriage a romantic failure or a post-romantic ideal?” Haag wonders. Translation: Is part of the essence of marriage that it’s always somewhat unfulfilling? David Popenoe, a former director of the National Marriage Project (and the son of Paul Popenoe, co-author of the famous “Can This Marriage Be Saved?” column in Ladies’ Home Journal), tells Haag that many people’s “view of marriage may be so unrealistic”—namely, romantic and narcissistic—“that they’re doomed to failure.” Haag’s mother tells her that “there are worse things in life than being bored and unfulfilled.” A woman who resigns herself to an unsatisfying marriage, in this view, isn’t limiting herself; she’s being realistic and mature.

Haag seems to believe this, which is why, in a series of chapters examining monogamy alternatives that range from asexuality to open marriage, the only real target of her scorn is the serial monogamist, who’s “always convinced that he’s in love with the next girlfriend … and that it will be different for them, in this marriage, this time around.” If he’d stop chasing this fantasy of romantic love, she reasons, he could maintain an intimate partnership with his wife—even if only for the sake of their kids—while enjoying a discreet dalliance now and then. In this vision of marriage, the happiest couples might well be the “infidelity tolerators”: those who can accept a one-night stand or three as long as the marital bond is the primary relationship. “These spouses are neither so romantic as to think that the atrophy of passion means they should divorce, nor so traditional as to think they must comply with the monogamy imperative at any cost,” Haag writes. The sociologist Jessie Bernard, writing more than 30 years ago, had a slightly different take. “If we continue to insist on sexual exclusivity as our marriages get longer, we may have to sacrifice permanence,” she wrote. “If we want permanence in marriage, we may have to sacrifice exclusivity.”

But the problem isn’t only that “infidelity tolerance” is a slippery slope: One day, you’re quietly overlooking a suspicious text on your husband’s phone, the next you’re fielding questions from the news media about his love child. It’s also that this “post-romantic” view of marriage isn’t entirely convincing. Granted, it’s impossible to know what goes on within the privacy of other people’s marriages. But, while they may be getting rarer and rarer, we all know couples who seem to be happily, enduringly married: the elderly couple who hold hands in the street, or the assisted-living resident whom I once heard proudly brag that she and her husband had had sex every day of their marriage. “What is a mystery to me,” Haag confesses, “and a thing of beguiling beauty, is the genuinely sexually contented long-term marriage—a monogamous dam lovingly constructed to manage the wayward lusts of nature.” Unfortunately, it’s the one phenomenon of contemporary married life that she chose not to investigate. But the fact that it still exists suggests that the old rules might have some value yet.

Ruth Franklin is a senior editor at The New Republic. You can follow her on Twitter @ruth_franklin.

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