Advice please, sensitive subject

I've been with my partner for nearly a year now, I have 2 children and he has 2 children from a previous relationship. This however centres on his 8yr old daughter. She comes to stay with us every 2 weeks, which is fine. We started trying for a baby together pretty much straight away, we've known each other for 30yrs as our mums were good friends. I got pregnant 6 months ago and we were over the moon, we told everyone straight away as soon as we found out including the kids as we were so happy. His daughter came to stay the next weekend and everything was okay, I was lay on my bed as I wasn't feeling too great and my partner told his daughter to let me rest as I wasn't too well, a few moments passed and she came running in the bedroom and jumped onto the bed and onto my stomach then dug her elbow right into my lower left side as she was getting up, it really really hurt. I came out with a bruise about the size of my hand within half an hour and decided it was best for me to go and get checked over, whilst at the hospital I started bleeding and the doctors confirmed what I had been dreading, I was losing my baby 😢 The doctors also wanted me to have an internal scan within 3 months to see if any damage had been caused to me internally as the trauma to my stomach was quite severe, his daughter isn't the smallest of kids at 8 and has already been told by health care professionals she needs to be on a diet as she's wearing clothes that are for 16yr olds but it's not my place to mention her weight thats between her parents. I had my internal scan just over a month ago and my doctor rang me yesterday with the results. I am very unlikely to get pregnant again, the trauma to my stomach has caused scarring on my uterine lining which pretty much makes it impossible for me to carry a baby again, I'm heartbroken amd devastated. What makes me more upset is that his daughter said she jumped on me on purpose as she doesn't want another brother or sister. I can't help but feel hate towards her, I don't want her at my home anymore. I feel myself getting angry everytime I think about what she's done to me, it's driving a wedge between me and her dad too.

Sorry but needed to get this off my chest