My g/f wants to go to a club?

Well I've been with my girlfriend for the past 6 months and we went to a club only once, and that was the very first month. We havent gone anywhere, but now she would like to go to a club again. I'm sort of afraid of going, maybe because I'm scared she might run into her ex or plainly just get few new numbers. I think she'd never cheat on me but am I too afraid of losing her? Should I just be lose? I know she wouldnt go to a clulb with out me, the idea of another man trying to dance with her or even talk to her pisses me off..