I don't mean to be a downer here, but I do want to be honest with you. I think the fact of the matter is that you can not ever help a person, until they are ready to help themselves. Not unless the person is a danger to self or society and you have to have them hospitalized. Even then, once they leave the hospital, it is their choice and responsibility to continue meds and seeking help. Which many people refuse to do.
So, don't be hard on yourself. Take care of you, and allow him to take care of him. If his behavior is affecting you badly, then get out of the situation. You can't change anyone else. You can only decide what your behavior will be.
I will pray for your safety and well-being. I wish you the best of luck with whatever situation you are facing. God bless!