Hello Dream23
Welcome, I am sorry to hear of what brought you here, you say that your sister’s daughter has been in crisis since breaking up with her boyfriend, I guess that she is grieving the loss of that relationship. Does she talk about it, and if she does do her parents validate her feelings? Validation is a very powerful tool when dealing with someone who has BPD.
Do you think that your sister would join bpdfamily? She would get lots of help and support with learning how to deal with her daughter x