Child Support and Visitation...I need advice?

My ex husband is an alcoholic... On numerous occasions we have had physical confrontations. He drinks around my daughter when he has her. (Which I will go into to more details in a minute), lives in a one bedroom apartment over a bar with HIS girlfriend and her son. My daughter goes on her "weekends" clean, showered and tummy full. She always comes home dirty smelly and hungry. He is never consistant on visitation with her and unless she is physically in front of him she doesn't exist... No phone calls, never involved in school activities absolutely nothing. Currently he is 3 months behind on child support and rarely see's her... Do I have a right to ask him to sign over his parental rights...I have full custody and now work 2 jobs to make up for the loss of support....My daughter has ADHD and this in and out of her life that he does is not helping her...I grew up with a father who was in and out and it's not fun and I don't want her to go thru the same heartache i did... I need some advice. Sorry for being all over the map on this but I have so much to squeeze into a small window without boring everyone....Thank you in advance...A