oh boy, I have this issues too. When I meet new people/start dating, I'm somewhat hypersexual (hypomanie often does it's part).
But the more I know people, the less interessted in sex I am. At least with them. Doesn't matter if it's a crush or a loving partner. The more intimate we are on an emotional level, the less desire for sexual intimacy.

I don't remember a time when this was not an issue, but beside trying to figure this out with my T, my partner helps me with the good old "no pressure".
It's really crushing when you are all "what is wrong with me" and your partner pokes you with a stick "is it me? why are you so? do you REALLY don't want to..?"

I think the most important point is that you both are happy with the arrangement. It's okay if you want to have sex in a marriage, but if he doesn't want to, he should not feel pressured to do it. And you should not be condemned to live a sexless live.