Should she be able to keep her

So, from age 5 to 14, I lived in a home where I was physically and emotionally abused. I lived with another girl who has slight mental retardation. She wasn't abused ad much as I was but maybe it got worse later. Anyways at 14, i got real sick of her shit and left. I told them she abused me and they took me out. She was never convicted, but i showed scars and marks ( that i still have) from her abuse. The other girl eventually started running away abs was put into another home. This year she went back to her (she was adopted, I was too but it was reversed). I found of that she ran away again recently. I feel like she's still being abused. My question n is should the woman still have the rights to her even though it was Proven she abused me? And her ( since she was taken out and poor into foster care)