I am a single mother, how do I get my man to be forced into payin me some monthly money?

Its hard and not fair that I have to raise my son all on my own. I know many of us (whitney O) have gotten ourselves into situations we arent pleased with, but there has to be an easier way. Why arent men forced to held accountable? Why should we have to do all the work while they get to go off and enjoy being young?