He sounds brainwashed because they lied about me and want us separated.
No they didn't lie. Read your post again. None of this is good for you and he can't ever recover while all this drama between you is going on. They want you apart for a good reason. I would focus on getting well yourself then you will see how this "relationship" is not one, that you were not put on this earth to accept abuse and verbal aggression off ANYONE and how you need to let him go. The place is not making him abusive. He just is. Your involvement with him is not helpful that is why the place he is in wants you to stop.