It appears that you really, truly love him. But (IMHO) it appears that that there are signs of co-dependency in your post.

I believe that he would benefit from seeing a licensed therapist and perhaps being on some med. Forget the idea that it is a sign of weakness to seek help. Only when more and more of us do - that is when others will understand that it takes courage and strength to ask for help.

IMHO - You can't "fix" him - no matter how much you love him. And you will eventually become exhausted and worn down if you are his only outlet for talking about his issues.