You can't help him. You can't fix him. You should move on for your own well being.

I had this exact relationship about 10 years ago. In fact it's so eerily similar that it could be the same man. I loved him so deeply, but he was mentally ill and it took me a long time to accept that. I was always giving and he was always taking from me emotionally. It was and exhausting and unfair relationship. In the end I knew that we would never be able to be happy together and that he couldn't meet my needs. I had to convince myself that I deserved better. I also had problems staying away from him for long. I had to cut all contact with him and ask him to do the same. I told him not to pick up if I called and not to answer the door if I stopped by. It was so hard in the beginning, it got easier after 6 months, and after a year I hardly thought about him at all. After 6 years we had a chance meeting and all that chemistry came right back. I decided to give it another go. I figured we were both really changed people. Sadly, he wasn't. Only this time I was more self aware and mature and I knew not to compromise myself for another person. I told him that I hoped he could be happy one day and wished him the best. I still care for him deeply, but only as a friend.

Your guy has to decide he wants to help himself. He is just not there and he may never be. You're only delaying your own happiness by waiting for him to change. He's only going to continue to suck you further into the dark hole that he's in.