Of course, to say that "this is just the way some women are" is never an explanation. I would say, "we don't know what it is".
But I also don't find it convincing to make the default assumption that for a woman, it is some issue about the marriage. Would you make the same assumption about a man with ED? Is the best "assumption" that a man has ED because of issues with the marriage?
Though you didn't say it exactly, I get the impression that you're buying into general thinking that if either the man or the woman isn't functioning sexually, it's most likely the fault of the man. Besides, the man can just pop a pill.
