It's Awkward When I'm Around This Girl.... Should I Talk To Her?

I used to be good friends with this girl but now we don't talk. We went to prom together last year, but then this year she rejected me to homecoming. We sit at the same lunch table, but I still haven't talked to her for 4 months. Sometimes I even sit right next to her, and we don't speak a word to each other. Oh, and she's always twirling her hair when I'm around, I don't know what this means. It's really awkward when I'm around her and I don't like it. Why can't we be friends like we used to be? Should I just suck it up and talk to her??