I think it comes from ingrained beliefs about women’s role in the family. A lot of women come home to the second shift, where after a full day at work they do all the housework. In a lot of couples I’ve known (and relationships I’ve been in), there’s this thing where the guy says ”I’d clean if you’d just tell me what to clean!” And a lot of guys jokingly refer to watching their own kids as “babysitting.”
Doing all the housework yourself is exhausting. Repeatedly asking another adult to do every little task is also exhausting. Housework is dull, repetitive, and thankless, and the idea that women are “just better at this stuff” is deeply ingrained. There’s an article titled She divorced me because I left dishes by the sink and the gist is that when you have to ask someone to do a little thing again and again and again, and it never happens, and you have to do it for them, it’s like death by a thousand papercuts.
Raising children also comes with hurdles for women, like inadequate maternity leave and the fact that women are more likely to leave the workforce after having children. Anecdotally, it seems like women are more likely to move for their husband/ boyfriend’s career than vice versa. These career gaps penalize women later in life if we ever decide to get divorced. Women are encouraged to identify with motherhood and marriage from the time we’re given our first play house to the massive wedding industry. It’s rare to see men whose lives revolve around being a husband or a father in the same way. These choices work for many women, but it’s not just a financial sacrifice; you’re also trading away some of your personal power and independence to take care of the family.
It seems like the default is for women to bear the brunt of these sacrifices. A lot of couples are progressive and work around this, but many don’t. Stress, overwork, and feelings of self-sacrifice can curdle into resentment really, really easily, and it’s almost impossible to enjoy sex if you’re feeling resentful toward your partner. (In evolutionary terms, we’re supposed to seek out a hot sexy man who can take care of a family. The guy who left his a wet towel on the floor for the umpteenth time until it grows mildew is neither.) The way the nuclear family is set up, most couples have joined finances and big financial obligations like mortgages together, with no extended family support system nearby. That makes it onerous to leave a partner who isn’t making you happy anymore, to the point where it might seem easier to just have sex that you don’t want. Like, you’re weighing changing your entire life against one more night of bad sex.
A lot of people fall into a pattern of her not wanting sex, him pushing for it all the time, and her grudgingly giving in, which makes the resentment so much worse. Once you’ve reached this stage, having sex with this person is an incredibly loathsome feeling, like dipping your body in pond scum.
I’ve seen and experienced this kind of thing enough that it’s put me off relationships for a while. Eventually I hope to find an equal and happy relationship, but for now I am much happier single.