My unborn twins were killed by someone who was like family!?

My name is Tiffany I am now 26 years old. My boyfriend and I were taking my child to spend the weekend with kids she called her cousins. I grew up with this girl my whole life and we always helped her with a place to live and getting her kids back. One night we were all going to spend a long weekend together and her daughter was taking pictures with her moms new camera and she took the camera from the eight year old and couldn't get the pictures to come up and she started yelling at her and calling her a piece of **** and saying all she ever does is break things and she drew back to hit her so I stepped between them and she shoved me into the counter it cracked a rib and sprung my elbow but most of all it killed one baby and tore the placenta lose on the other one. My mother would let me call the police because she didn't want DCF to take this girls brother away because they had just got him back. The woman the killed my babies said that she didn't care! Now every day I have to deal with her she only live a few mobiles over from me and she is trying to make me look like the bad guy and even has my own grandpa thinking that she was in the right! He don't seem to care that she killed my babies. Now she keeps her kids away and is hurting my little girl because she sees the kids around the park everyday and isn't aloud to play with them after playing with them every day of her life for five years. It is hurting my daughter and me I don't know how to deal with the fact that she killed my kids and got a way with and it don't care that she did it! I could really use some advice on how to deal with it!