I agree that in an ideal situation both partners are meeting the emotional and sexual needs of the other, but it's also a sociological fact that many men, once they are married and "have her" stop treating their wife like a lover, who needs affection, connection, and to be wooed a bit, and start treating her more like an approved sex dispensing machine that you happen to live with. This kills women's libido - so if she is no longer interesting in having sex with him, chances are high (not universal - but high) that it's because he has long ago stopped meeting her needs. He's probably not intentionally withholding anything from her - he's more likely just going along with a cultural script that he's been messaged his whole life - but the results are going to be the same. She's not "withholding" either - she just has no real interest in being with him sexually under those circumstances. The fact that he can't see his likely large part in this equation is what I'm speaking to.

I was recently at a reunion of college girlfriends and a huge percentage of them are essentially married to Homer Simpson. He sits on the couch in front of the TV, eating, and watching what he wants to watch, while she fixes herself a more well-rounded meal and eats by herself in the kitchen at the table. These guys have no interest in co-creating a relationship any longer. They just want to do what they want to do, and seem to believe that their wives exist to make their lives nicer, without reciprocating. One husband of a friend watches only things she isn't interested in, but demands that she sit in the den with him anyhow - so she just reads a lot.

Overwhelmingly, women who have been divorced or who are widowed are not interested in marrying again or even cohabitating. Some still want relationships, but they want greater autonomy and control over their lives, and they want their partner to have to make some effort to spend time with them. It seems like too many men are oblivious to this, and believe that as long as they really do actually love her, a sex-dispensing house elf ought to be satisfied with that arrangement. Most aren't. My college friends aren't looking to get divorced. They do still love their partners, but a lot of them sleep in separate bedrooms and I find that incredibly sad. It makes me really value the on-going romance and deep friendship that I have with my husband.