Absentee Father... mom seeks custody

I am hoping that someone out there can help advise us. I have a son who is 6. Between 1996-1999 the bio-father did not call/visit/see ANYTHING to do with this child. The child had major medical problems and was in the hospital and in special care for the first year of his life. I made many requests for the father to help with the situation, however he would not. I ended up taking him to court for child support to gain medical insurance. He never filed for custody of my son. We did attempt mediation, however when the final papers were drawn up, he never signed them. He never visited this child EVER...He sent his wife instead... long story short, I moved away and married. In 1999 I moved back to my home town and divorced my then husband. The bio-dad of my son (then nearly 3) decided he wanted back in the picture. Me being the nice forgiving soul, I let him. We eventually began to date. The bio-dad only saw the son during the 8 months we dated... and only when I brought him around. He never came around voluntarily... or offered to help with anything, including bills or past medical bills which amounted to over $50,000. I was deeply in debt and eventually filed for bankruptcy. A year of silence after our 8 month dating period, ... no phone calls, no visits, no presents/cards etc...and when I was getting ready to move away for school, he reappeared and we began to date again. Another 8-9 months when he saw my son because I brought the boy around. He did not come over to visit, call to talk to him, or anything. At this point I had had enough and ended the relationship. That was 11 months ago. He began stalking us as a family, and I had to get a restraining order in order to legally protect my family. Shortly after I had ended the relationship I met someone else. He cares deeply for the children, myself and my family. We married not too long ago. The bio-dad has not had contact with my son... the first 6 months he did not attempt anything, he did attempt to bring a birthday present by a MONTH after the birthday, however I would not speak to him. He had been stalking us and following us around for 6 months determined to "get me back". I obtained a RO after this. The past 4 months the bio-dad has not been legally allowed to contact us... and we will have this for another 2 months when we will either have to re-apply or take another path. The lawyer I spoke to several months ago said that the court would not take into consideration the following: A. bio-dad did not have any contact with the son first 3 yrs of life B. bio-dad has never paid any of the court ordered medical C. bio-dad is abusive D. bio-dad has had only intermitent contact but only because I physically took my son to see him, bio-dad has NEVER taken the initiative E. bio-dad has not attended any of sons social functions or school functions or parent/teacher functions F. bio-dad has never filed for custody G. bio-dad has not paid consistant child support and can not afford to The lawyer told me that it looked like a "get back at him" case and she would not take it. This is NOT true. I feel that we have a good case, and I do not understand why the court would not consider that the bio-dad has a violent background, has stalked us for nearly a year (we have LOADS of witness'/evidence), and has threatened my son on several occasions. My son does not want anything to do with him, he feels that my husband is his "dad" and is afraid of the bio-dad. Help! Ember