What if she stops doing something else? I'd deal with that if it happens. That assumes there's a more general uncaring aspect. Rather, it's clear she's had difficulty with the sexual aspect for a long time.
I can only imagine that it must feel like a lot of pressure for a woman who has already had some issues around sex, has never had an orgasm, has been made to feel bad about her sexuality because of the lack of it, has had many childbirths, and has gone through menopause.
Perhaps a bit like a woman accusing a man of not caring about her because he can't get an erection. And if the man doesn't go to the doctor and admit all this, I guess that's another sign he's really callous, no?
Not that I disagree with you, but seen as a symmetric standoff, I'm curious how you would support the concept that when one person wants sex and the other doesn't, it's the person who is refusing who is callous? Why is it not the person who is insisting on sex who is callous to the asexual person for not taking her revulsion to sex into consideration? Can't the highly sexed person go to therapy and learn to control his impulses or channel them? Not that I agree with the latter, but just curious how people justify it.
And this is one aspect which really turned my wife off in therapy. She quickly picked up on the implication that she should have sex, and that there was something "wrong" with her, rather than anything "wrong" with me for wanting lots of sex. So in this sense the therapy backfired on her, though it did make her more accepting of me as normal, even if she didn't want to participate.