Divorce & Child Custody

I have been Married for a year and half now. Followed by severe mental and emotional abuse by my inlaws and husband, and my husbands habitual drinking habits, and getting physically violent several times (even during my pregnancy) I had to walk out and stay with my parents throughout my pregnancy. There was also constant steering from MIL for baby boy. My husband in laws dint meet me at all throughout my pregnancy and denied to pay any of the medical bills. After their denial I had to fetch a job and earn for my bills with a lot of financial assistance from my father. They were spying on me and as soon as I delivered they confirmed it was a boy and came to see my child. husband refused to see me. After learning my child had health complications he clearly advised doctors that he wont be paying any bills. Now when the child is doing good after hard earned efforts from me and my parents he writes nasty mails and asks to come and see the child. I am worried about his short temper which might harm my child. **this is just a brief. Question: 1. I am shortly filling a divorce. Am I eligible for child support? I lost my job coz of my pregnancy. I am looking for another job now (son is 5 months). If I get a job with a better pay than him, will he still be liable to pay child maintenance. 2. I want him to access the visitation rights so that my child is not deprived of the father love but can he take the child out without mother's supervision? this I dont agree coz he has many bad habits and is very short tempered can have a negative effect on my child. 3. If he is not regular to his visitation hours can I get them negated? coz they may emotionally harm my son. 4. will his parents have visiting rights as well? His father had a history of psychological illness and is under medical treatment still. He also is very violent both physically and verbally to my MIL.