Should we go through with the adoption??

My husband and I are adopting a teenager that has lived in institutions most of her life. She now has a stable home environment but insists on pushing us away. She has made false allegations of abuse to authorities and to school, threatens to kill herself, runs away, steals and has violent mood swings. We have therapists and social workers but they are not much help. She has been ually and physical abused most of her life by her brother, uncle and birth-mom's boyfriend. Has anyone gone through with this kind of situation before? Has anyone BEEN this kind of kid before but has "healed" and become a model citizen? We have a month to decide if we should continue the adoption or not.