Wow, This is a tough situation. Unfortunately, you can't make that man do what is right. All y ou can do is a paternity test when the baby is born, and actually I think you can even do it before with an amnio. Child support is tough, too. Some men are just not responsible and will let courts come after them. Sometimes it is easier not to deal with co parenting. Then you make the decisions and worry not over another persons ideas and baggage.
Here is my story...I became pregnant at age 19 with my oldest. I made the mistake of marrying the father only to leave him by the time my daughter was 4 months old. The father was not a responsible, ratbional man. He chose not to be a part of his child's life and paid child support ( a meager amount) only after courts ordered and wages were attached. He only visited with her when I made the arrangements and I was travelling with her to the state he lived. If I never brought her to him, she never would have seen him.
The good part of this was that he never was there to argue about how I raised the child. He wasn't there for me to fight with and she never saw the negative. I remarried and my husband is her dad. Although I DO still try to collect child support...it still is his responsibility.
I wish you the best. You are strong, I can tell. It will be OK. Look at the positive. Join a playgroup and new mom's support group. There is a group call MOPS...it is a Christian based program for moms. I found a lot of support there and made a lot of great friends.