Don't feel down Rainboots. You're still young.

You've plenty of time. I know it sucks being single and watching other couples...there's nothing on this earth more I envy than that. But if you throw in the towel for dating, only then have you truly lost.
I think other posters have got it right...find a hobby or an interest that requires you to meet others. That's usually a good way to get the ball rolling.