I honestly don ' t think I can give advice without offending you , but I ' ve been where your daughter is in many ways . Please stop dismissing her problems , and try to keep an open mind and get her the help she clearly needs . You ' re her mother , you need to protect her and help her , not dismiss her or laugh at her problems . She is most likely reaching out to your sister because she is not receiving the right kind of love and help from you , and feels your sister understands her better . Forcing her to cut off contact from your sister won ' t help , either . Your daughter is still the same person you fed as a baby and cuddled as a fouryearold . Remember that . Unfortunately she has clearly been through a lot and has issues , and needs someone who will step up to help her or at least take the time to listen without judging or dismissing her . Please consider this carefully I wish someone had once given my own parents this advice , our relationship has never been the same since I hit puberty and started having issues of my own . Things could be very different for me had it been so . She sounds like she has depression and needs consistent treatment as well as a loving and supportive mother . You can be that mother , it does take a lot of effort but you can be that mother from now on if you make that decision every day . She disclosed a sexual assault that affected her please don ' t laugh at those things , even if they seem small to you . You said she has Aspergers many times , issues are magnified a lot for people like her . I hope this helps , I am sorry if I did offend you , and I suggest counseling oneonone for her with a licensed psychologist specialized in mental illness , and family counseling sessions for both of you together . It won ' t hurt to include her brother , either , given what horrible things he has been taught by that boy you mentioned . Please consider your next move carefully .