I see it too often among my friends, and it's such a waste of time being afraid. If you really like her ask her out again, and as said before by another don't fear rejection. If she says no keep it moving. There's way more women than men out there so your odds are good if you don't let things like rejection rule your way of thinking. If she rejects you create space and opportunity for other girls to spark your interest. It's not worth it fawning over her, it could literally play out a whole lifetime. I'm 32 and I've got a friend whose been fawning over another friend for at least 10 years and it's pitiful. He's spends so much time with her(she's his best friend) that he compares her to all others and just keeps becoming more enthralled with her since no one measures up. Never realizing no one could cause she has a lifetime of closeness they developed and he's never given anyone else that much time. So don't do it, it's much better to get out and meet as many girls as possible, your far more likely to meet someone who really stands out and is special. Plus it's alot more fun that way. Lol!
