12 year old daughter struggling with friends betrayal and becoming obsessed! Help!?

I know this sounds tough, but children need to learn their own mistakes. You've told her, you've been a good friend, now she has to make her own decision and, well, get hurt. She will be down for a while, but then she''ll know better. I think that signing her up for lots of cles and maybe inviting lots of other friend's round is a good idea, but she's old enough to learn a tough lesson. Good luck.