what can i do?

:( Hello..I have a couple of things I need to know..I have a son that will be a year old Aug.28th..I made his dad leave in december because he was very abusive to me and not just that..he went to hit me while I was hold our son and hit our son instead..so I made him leave..so far he has seen his son three or four times sense december..he hasnt seen his son sense easter!!!! He dont call...he dont come see him....he dont pay childsupport and he has baught two packs of pampers sense decemeber!! What can I do to file for abandoment? He has his fathers last name and thats fine but he wont give his rights up!! I dont want to file for childsupport because I dont want him to have the right to leave with him if he ever wanted to..I dont trust him at all. He was in Iraq for almost a year before we got together and he has changed so much..he blacks out and hes abusive in every way...WHAT DO I DO!!!?? somone please help me