They are very weird!!! Part of it is that sex becomes overwhelmingly important to so many of them. It becomes the be all and end all of their life.
I am not saying that it is unimportant at all, but there has to be a balance here. I am friendly with a couple where the h has impotence issues relating to his health. They they love each other deeply and have talked frankly to me about it [individually] partly because when you are going through h*ll people see you as someone safe to talk to.
It has been tough for them, but they decided that it wasn't going to be a marriage wrecker - no way.
I feel very sad that our h's couldn't handle something much less serious than this with the same maturity . . .