It usually is expectations on me that is the problem. If I can't feel comfortable being myself around someone because they think I need to be the perfect fit for them...or else, I just suck in their eyes. Sometimes people really are not worth the stress. A lot of people are set in their ways and only they can change themselves. Find one or two that you can stand and they can stand you as you are and spend the rest of the time experiencing and learning.
I think I can only handle maybe three major friendships at one time. It's really all I need as long as their solid ones. Even one good friend is enough.