My question to you is, why do you want to be in a relationship like this? It sounds like all it is, is just stress and heartache. I don't think you'd want there to be any hope for it the way it's going.
From what you've described it sounds like your boyfriend manipulated you into moving in with him to take some of his financial burdens off of himself and put them on you, and then manipulates you to stay. You need to get out. It sounds like his has some issues to work out and no matter what he says and how he makes you feel, they are NOT your problem. He's just pushed them onto you. You have the power to leave and make a better life for yourself.
Solely, it is your decision, but I would strongly suggest you to leave him. He will do whatever he can to make you stay, but if you're strong and realize what is going on in the situation, you will be such a better person for leaving. You deserve so much better than what he's putting into this relationship. I wish you luck.