This is a weird spin, but if you're anything like me, thinking outside the box and not being appalled over everything like the average soft ass hoe nikkas these days:
You should be happy to have cultivated such a strong relationship with that person that you have the feelings you do. My disdain for the mother of my child is well documented here. I barely knew her, and had already tried cutting her off weeks prior to her rising from the bushes to send a 2 word "I'm pregnant" text. When I read the first sentence in the thread title I was ready to come in here and congratulate you, no bullshyt. It didn't even cross my mind that you actually cared for her because the pain you feel in her death is the pain I feel every time I remember mine is still breathing.
I say that to say, you made a child with love and have very fond memories of her. I can assure you that once you have had time to process this you and your daughter will be just fine. Mom's isn't hurting anymore and you have each other. I usually NEVER do this, but because I can somehow feel your pain even though I can't relate...R.I.P. Gina