For me, being focused on my AH and his issues is often like tunnel vision. I can't see or attend to anything else that is going on because dealing with his issues is so consuming for me that it takes everything else over and becomes priority.
The only person that we can control is ourselves.
You said that if he continues drinking like this then he won't have any money to help with your rent. So, assume that happens. Then what? Focus on what you can control and go from there.