I did the same thing.. I went to Gally in 96 and surely wasn't ASL at all. Once I got to meet people.. they were really obnoxious and would tell me I didn't belong in Gally because I Mainstreamed. I stayed anyway. I ended up having friends that was patient with me and has taught me so much. I came home using ASL. Thanks to my true friends that helped. I can see where there is a group. Group of INTELLIGENT, group of low function mind, group of athletics, group of drug-heads, etc. They just have their own preferences. As for me, I'm neutral, I'll take anyone in as long as they have respect for me and back to them. I've been in that situation where they tell me I didn't belong in that "group" which is fine because I wasn't comfortable anyways.
I know its hard but your friend will find her true friends and will help her out.