Your description sounds as though he's insecure. From experience, things that boost his sense of security are to increase his self-esteem (that's #1!) and show him genuine affection frequently.

He holds the key to increasing his self-esteem: intellectual or artistic classes, exercising, self-defense classes, writing, finding some activities that he can do & feel good about is crucial. As he does this, and you're still showing him love & affection, he will feel much better.

Very best wishes to you!