By the 40th year, every woman is menopausal. And as couples like yours disappear, the sampled population becomes, on average, happier and happier. What this simple act can do to relationships could be surprising. For every theory I've proposed here, I can see problems. The woman can't get more love than the man will give. But this isn't a study of single men or serial newlyweds. Women like to make eye contact and stay close after the deed is done while men want to roll over and, literally or figuratively, light a cigarette. Ever since the founding of the Kinsey Institute , conservatives have accused it of spreading perversion and destroying sexual virtue. It Releases Oxytocin This is the scientific reason. I know there's a lot of culture and socialization here. In fact, women love cuddling more than the actual intercourse. The man can't get more sex than the woman will give.