I know this may be difficult, but maybe you could reach out to this person or group and tell them where you feel wronged.

Maybe they don't know what they're doing, or maybe they do and they only treat you poorly because they know you won't say anything.

I had a friend who mistreated me, and I took it for a while, but one day I talked with her about it and how it was making me unhappy and she stopped.

It's scary to do but it feels good no matter their reaction.