You said she had issues when you got her. she is from an abusive home.
We had a foster son that came from abuse and though we did what we could, after he graduated from high school he left and disapeared for several years. Left a note that said he just didn't get the family thing and didn't understand us loving him and so he needed to get out. He went back to his alcoholic abusive father for awhile and then lived in his car for about a year. Ended up in jail and somewhere along the lines came to his senses. Married now with 3 beautiful girls. Calls us Mom and Dad and our place home. He is 28.
I guess that you have to have the faith that you gave her what you could and some day the seeds of love and acceptance you planted will grow and she will come around...