Why do I want a boyfriend so much?

I know this sounds stupid and cliche - a teenage girl feeling estranged from her life. But I just feel so lonely. I am almost 17 and will start university in Feb of next yr (I live in Australia and hs students grauduate at different times). Anyway it just seems I never get noticed. lately all that's been on my mind is that fact that I dont have a boyfriend and that I want one so much. I am quite mature for my age and more perceptive than my peers, and I'm not shallow. So I don't know why I'm so caught up in this? I've never had one, but it seems everyone else has one. It just makes me wonder why I put effort in my appearance, as I know I'm pretty average looking anyway.