I can answer your question although this is a not formal therapy. You have indicated that this is not a healthy relationship and from what you describe I would agree with you. What is troubling however is that you recognize that this is not healthy but you still feel the need to be responsible for his health. No one is responsible for someone else's health. We all as human beings need to be totally accountable for our health. By feeling you are responsible you run the risk of always feeling obligated over having a normal giving relationship. Until you own only your part of this conflict you will always feel it is necessary to fix all the problems and cater to his abusive personality. In fact he is responsible for his own self and anything that comes with that.
You need to decide what you need to do and how that is best for you. If leaving eventually brings you peace of mind then that is what you should do. As long as you have to cater to him you can't fix yourself. His ability to constantly ruin things in your life indicates how selfish he is. You need to take care of you first.
As far as your family they will forgive you if you are on your own. They will begin to see that you made bad choices but that is in the past. Families always come around but you have to do the right thing first.
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