Getty Images Divorce papers filed by singer Britney Spears in Los Angeles Superior Court on November 7, 2006

Not long ago, after giving a talk about the growing number of women who are breadwinners in their marriages, I was approached by an audience member who identified herself as a lawyer. She said that she was definitely seeing this trend in her practice — nearly 40% of working wives now outearn their husbands — and that while economic power is a good thing, overall, for women, it can have one negative outcome many don’t anticipate. Among her divorce clients, she said, more and more were women who found themselves ordered by a court to pay spousal support to ex-husbands. “And boy,” she said, “are they pissed.”

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That these women are angry is to be expected: men don’t like paying alimony either, and writing a check every month has long been, for men, one of the prime impediments to postmarital bliss. But their reaction also suggests that women, while eager to benefit from progress and expanded opportunities, are not so willing to accept the more painful consequences of our success. What’s sauce for the gander is, alas, sauce for the goose. It may or may not make it easier on these check-writing ex-wives to know that they are part of a larger movement: the degendering of alimony and divorce, which is a natural outgrowth of the degendering of roles in marriage.

Once upon a time, the point of alimony was clear: it recognized the essential deal underlying marriage back in the days of “separate spheres,” when it was a husband’s role to provide, and a wife’s role to stay home, raise the children, run the household and enable the husband to be hard-working and high-earning. The economist Gary Becker famously argued that this was how couples maximized their efficiency: dividing the labor enabled both to succeed in their respective spheres. When marriages fell apart, alimony provided legal and economic recognition of the fact that a wife had sacrificed her earning power to maximize that of her husband and enhance the welfare of their family.

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Now that the separate-spheres marriage has been replaced, in many cases, by the dual-earner version, there is a move to abolish permanent alimony altogether. As this TIME story documents, in some states the crusade is being supported by second wives, many of them working women, appalled that their earnings (in some cases) are going to pay the alimony of first wives who stayed at home to raise children. The animosity between those two groups is in some ways one more iteration of the mommy wars — the lingering gulf that exists between women who work outside the home and women who work within it. But it’s also a sign that the bargain of marriage has changed and splintered; there can be any number of deals now, including deals where the mom stays home; deals where both spouses work; and increasingly, deals where the woman is the primary earner. The ranks of stay-at-home dads are small, but they have doubled in the past decade. And in dual-earner marriages, there are more and more where it’s the wife whose career takes center stage and the man’s that becomes supplementary.

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As a result, it’s not only women who are wrestling with new emotions: after publishing a book on female breadwinners, I also heard from a bank administrator who quit his job after his first child was born, enabling his wife to more fully pursue a lucrative career as a lawyer. He said that he loved and trusted his wife, but sacrificing his career and paycheck did make him feel “rather vulnerable.” Just as women may find themselves angry, men may find themselves uneasy, as both sexes get used to the fact that some of the old patterns will persist, shorn of gender, and so will some of the old obligations.