Oh god, I am so sorry. You have been through hell and seems like your fiancee just wants to double down on your misery.

First, though I don't know your mother I do know that YOU are not the reason she committed suicide so wipe that thought out of your head.

You are going to feel some relief even if you are sad. This woman is a terrible person. Can you also get custody of your child? That child has been indirectly abused by her as well for the way she treats you. Can you file a court order for custody? Put your love into that child. She doesn't deserve you.