Hi LostInParadise92,
I always hear this exact thing from friends that move to Los Angeles, that it's a place where you find out real quick who your friends are. I also notice though, that their friendships that have stood the test of time tend to be really solid.
Regional tendencies aside though, I am in the same boat. Haven't found a solution, but I really relate. An unfortunate barrage of sequential events in which others have betrayed me in some way seems to have turned off my ability to trust anyone but those who have long since completely proved themselves to me.
What I've been trying to do, is re-establish what good boundaries are, for me, while also opening myself up to more varied social situations (my newest thing is support groups .. like the Marla Singer character in Fight Club, although I'm not attending anything inapplicable to me) in order to exercise those boundaries. But it still feels as a loss, within myself, I suppose because the greater faith I had in others before was part of who I always was.
I've had to recalibrate before, but it can be overwhelming, as I am finding this time around.
Good luck!

vonmoxie
“I hold this to be the highest task for a bond between two people:
that each protects the solitude of the other.”
— Rainer Maria Rilke