I'm very happy for you that your daughter's birth went well and you have a healthy baby girl! I've got 3 girls myself, not babies anymore, 2 married and the youngest just turned 18, but it brings back memories of them when they were so young. I hope your daughter continues to be a healthy and happy baby.
In reading your posts, I understand how you would feel resentment towards the father. I think back about how I felt when my ex-wife was unfaithful and left after 23 years of marriage, and how irresponsible she has been in so many ways since then. I had a lot of resentment towards her and I know that I even showed some of that to my kids in the beginning...I've had to work hard at letting go of things and forgiving her, which has been difficult because she has continued to do things that aggravate the situation. I've found that forgiveness is an ongoing process, and when I think I've let go of it all, as time goes on I find there's more that's come to the surface that I need to let go of. I've also found that in the process of letting go of hard feelings and resentment I am the one who gains the most benefit of it.
My advice, should you wish to hear it, is this - there are 2 relationships here: Your relationship with your ex-fiance, and your daughter's relationship with him as her father. You feel a lot of hurt towards your ex-fiance, that you supported him in many ways but he did not support you in return, and you may feel that he abandoned you in your pregnancy, wasn't there for you....all that may very likely be 100% true and you may have good reason to feel as you do. But that is between you and him, not between the daughter the two of you created and him. It might be easier for you to think of this baby girl just as your daughter and to raise her on your own without what you see as interference from him or his family, but is that what is best for her?
In the best of worlds, the best thing for a child is two loving parents, together as a family, raising the child as a family. Unfortunately in the world we live in that often doesn't happen, and it's not happening in your world. So, given a world in which a man and a woman create a child, but cannot be that family that raise the child together, the next best thing is both parents actively involved in raising and loving the child even though they aren't living together.
I suspect the father wants to be part of your daughter's (his daughter also) life. He may not have shown that to your satisfaction or been there for you or the baby to this point, but frankly it doesn't sound that you have encouraged that from him. He probably also has his own issues with you that he is likely allowing to get in the way of things. The point I'm trying to make is that whatever the issues are, they are between you and him, not between you/him and the baby.
I hope what I'm saying does not come across as judgmental or condescending, for I am not thinking in those terms - I have no judgment against either of you. I only have what is in the best interest of your daughter in mind. I know from what you write now and what you have written in the past that you are a good, loving, caring mother...you have been that caring mother for your son and you are/will be to your daughter as well. And from what I remember of what you had written about your ex-fiance, you saw him as a loving and caring father to his children, and I would venture to guess that he still is. So...as hard as it is right now, try to see your relationship with him separately from your daughter's relationship with him. She deserves a relationship with her father, and he deserves one with her. Give that a chance to happen.
I wish you all the best Elizabeth, and your daughter as well. Please take care.
Jim