I don't think that spending time apart is necessarily the problem in a long-term marriage. I have two friends whose husbands are passionate about fishing and competitive golf. Their children are grown up and neither of them question their marriage on account of it. I have two other friends who regularly travel to different destinations from their husband - both volunteering abroad so low cost.

I think the problem is that you are angry and frustrated with him - and that he isn't responsive to you on the same emotional level, except by fighting. Also blurred boundaries on your side.

I wonder if he is someone who always needed his own space - yes actually needed that - or whether he is hiding his own needs and emotions in a corner because he's afraid of them. I do wonder whether he needs gentleness, and perhaps support from male peers, to sort himself out emotionally. I have a friend who is very different from your husband = hyper-social, but he is terrified of his deeper emotions, and does all sorts of dysfunctional stuff to avoid them. He is starting to know this behaviour won't be tolerated for ever.

Your h sounds withdrawn, and in need of some gentle external support and understanding. Seems like he did talk with his doctor, and his doctor saw this about him.