You ask, should you "keep fighting for our broken relationship for the sake of our love." It is not like you can argue someone into being in love with you; "fighting" for the relationship is not going to put love back in his heart if it is gone.
He cannot legally walk away from the child-support obligation, don't roll over and just watch him shrug the obligation off. But in terms of recreating or reviving your relationship, if he no longer wants to be with you, you have to understand "our" love is over. Fight for the child support but don't expect you can "fight for our broken relationship" and magically he will love you again.
Hi there. This is a difficult situation hon. I'm sorry you are going through this. Sounds very stressful. Bottom line is that he does not want a child right now. You have to look at your own options. Men have the luxury of walking away and women are kind of stuck left holding the bag. You have to think worst case-- if he goes-- do you want to raise a child alone? Give baby up for adoption? Go through with the pregnancy? I think you need to focus on the big picture of having this child and if you have to do it alone, is that okay with you. Then if it is, you can risk if he steps up to be a part of things or not. If he doesn't, do make sure to take him to court for child support. That's his duty. But you can't make a man/boy want to be a dad. And he clearly doesn't at this point. good luck!