It seems he's more addicted to you and terrified of being alone than really "in love". In this case, the best you can do for him and yourself is shut him off completely. If you give him some attention out of pity, it will never be enough. And it would keep feeding him false hopes. So as painful as it can be, now is the time to be objective and block him off for his own good. Maybe in a couple of years you could even be friends, but not now. He has to confront himself with his own monsters, deal with his own issues and he can only do it alone.