Plus, how do you know that all parties wouldn't resent the interference? While I agree that it didn't sound like a healthy relationship, the amount of time that the OP spent around them really wasn't enough to judge the true long-term dynamics of their interactions. The OP was understandably uncomfortable about the situation, but you can't really "help" someone who doesn't want to be helped. If the young man had a job that he should have been at but wasn't, it doesn't exactly sound like he's being held prisoner. The OP says there is a child involved, does he even know for sure whose child she is? (Just for reference, my son was 4 years old and my daughter 2 months old when I turned 40)
I don't know about the OP's area, but our local domestic violence shelter does have facilities to house men, too. While men being abused is less common than women, there is increasing awareness of the fact that it does happen, and the "outreach" methods being practiced address that possibility as well. What the OP has said about the young man suggests that he prefers to play a "childish and irresponsible" type role; maybe he'll grow a backbone and decide he wants better for himself. Until he does, though, there really isn't anything a complete stranger can do, especially one with as little information to go on as the OP has.
