Lonely

So I'm a freshman and I go to an all girl school. My problem is that I'm having trouble accepting myself. Sometimes there are periods where I believe that I'm beautiful, and then to support that (because im 15 lol) I look for validation.

I'm kind of awkward and I've always been that girl that guys wanted to be friends with, but nothing more. And recently I've been noticing that there's a need in my head for a boys validation. I don't want it to be this way, and I'm looking for some reassurance.