If my boss didn't pay for my health bill and asked me to work while at the hospital I would definitely not let it go like that, you are a human being, moreover, you are helping him to get money. And you are almost getting no money back.
As about lawsuits, it greatly depends on how you focus it. You are being exploited, you know it (and he knows it). You could probably sue him right now. And telling your colleagues about how work was like there is not unethical, nor illegal, it is helpful for them.
Couldn't you just balance on paying for more bandwidth (don't know the prices where you live) with just more freelancing? When you say "bills" you mean just that, or include expenses like food and the like?