I definitely understand what you mean, though not necessarily in this situation. I've definitely had times where I wished I had friends who would accept me for who I was and care for my unconditionally without trying to change me. I have never had a problem with polyamory and my friendships, but I believe thats largely in part to how I act and talk about it with my friends.
I was wondering, have you tried coming out to your friends about being poly? If so, what has happened? If not, well, why not? I would like to hear more about the situation if you don't mind sharing, and could maybe give some advice or help in some way.
I think everyone needs to have friends in their life who they can talk to and count on, and who they don't have to hide large parts of themselves from. Hopefully you can achieve that with your friends or find a social circle you feel happy in.