How to handle "mean girls" at a young age

I say "mean girls" because I really don't feel like these girls are truly mean.  I think they are so young and there is so much out there telling them how to act even if they have the best parents teaching them otherwise.  I just get so sad that my 8 year old comes home every day talking about how she is being treated.  That girls she has called friends are kicking her out of their circle saying she is not good enough and laughing at her.  I have told her to talk to some of them, tell her how it hurts that they are being so mean, that she thought that they were friends.  We have pep talks in the morning on how she can deal with it that day, but it never fails.  I pick her up from school and ask how the day went.  I ask if she talked to her friends the way we talked about and she said she tried but they laugh, roll their eyes and run away.  And I have seen it first hand.  The dirty looks, the pushing, it angers me.  But what do you do?  I am sure that any sort of confrontation to the parents wouldn't work out.  Would they think I am taking sides and thinking my daughter is an angel?  Would they actually talk to their child and teach them how to be friends with everyone?  I don't know.  I think I am just frustrated.  My daughter has gone through so much in her 8 years, I feel like she deserves to have great girlfriends.  Friends who will have her back and not turn on her when they feel like they don't need her anymore.  How have you handled this?  Would you be open to listen to a parent who comes to you about your child?