I know 100 girls like this. It’s okay to hang out with girls.
I totally had this mentality in high school, but it was largely because I felt rejected and ostracized by other girls. Sort of a reject them before they reject you sort of thing. Oh, you think I’m weird and loud and slutty? WELL I DON’T EVEN WANT TO HANG OUT WITH YOU. Also, all of my close female friendships inevitably caused me more heartache than my male friendships, though this is probably my own fault. I hate girl-on-girl crime and I hate that it let me discount some girls that probably could have been good friends. I wish I had known better.
Definitely have grown out of this though. I’m 21, and while my best friend is male, the vast majority of new friends I’ve made in college are strong, beautiful, cool, awesome women. Yay!