Suggest Treatment For Depression

I have two children. One boy age 25 and girl age 21. I have been estranged from my son for 11 years due to PA. I found out a few years ago from my daughter that she was sexually abused by my son at age 9 along with some friends of my sons. I've always felt that the father of these two had sexually abused my son and could never prove it as son lived away from me. Eventually cutting all ties from me. Unfortunate and devastating situation. But now my daughter has gone to live with father and son! My daughter now blames me for every issue she and her brother have. I don't understand, why victims gravitate to the abusers! I was a good mom, not perfect, but divorce caused horrible pain for my kids. Why am I now the one they blame for everything?