Regrets, have you looked into midlife crisis? I know he seems a bit young, but I've heard it can be early. I hear some of my husband in the story you tell. Mine has not gone so far as to say he doesn't love me, but what really strikes a chord is how you say he doesn't know why he feels this way.
Mine doesn't know why he's dissatisfied either. I can tell him everything that is wrong on my side. I can tell him everything he can do to relight the emotional connection from my end. But all of my questions to him come up unanswered. He doesn't know why he feels this way. He doesn't know what I can do to help. He doesn't know why he isn't interest in sex. He doesn't know! Sometimes he writes down the questions and says he'll ask his therapist. Aaaargh.
I'm still learning how to deal with this. Good luck to you, and check out the forum on Mid-life crisis if you haven't already. It may be nothing of the kind, or you may find something there to help. Reading it gave me at least a small measure of peace.
