I don't want him hurting others like he did me. I don't want others to "go crazy" in the process like I did.
You are assuming that the other woman he is with are just like you. That they are going to fall deeply in love with an unavailable man and then be unable to detach from him like you. Who says they are anything like you. The last one he was with already knew he was an alcoholic and she slept with him anyway. Maybe it’s just sex, some woman can have just sex without developing a deep emotional connection.
It has nothing to do with not wanting to be alone (although I can't do that either) and so much to do with just how SICK he is and how he's basically a waste of life at this moment.
If you feel he’s such a waste of life why are you wasting yours on chasing after him, trying to keep other woman out of his life with your warnings and accepting whatever crumbs he may or may not throw your way?
You don’t seem to want to put as much effort into you as you are putting into him. You admit you don’t like to be alone yet being with him leaves you very lonely, hopeless, angry, hurt and in despair.
The longer you continue to hold on and be dragged the more battered and bruised you will become. You rally should address your own addiction, get hold of your own sickness, make changes in your own life instead of hoping and waiting for him to.