Going for low-cost legal aid is fine, but maybe an interim step you could make is a free consult with an atty. to ask a few questions and see where you really stand.
I get that you are kind of worried about him (alimony or not) but at some point one of you has to worry about you! And that is only going to be... YOU!
It's hard to start putting the boundaries in place. For the first few months after D-day I still played the part of ex-shat's conscience. Took a while to figure out it wasn't my job anymore and that I should start putting all the effort I spent on ex-shat on myself instead.
The first steps are tough. We just have to force ourselves to take them and have faith that we are starting on the path to a better place.