Gachetemas
I think it's not about a girl, Kurt Cobain. Something else is at its center and the girl is just the metaphor. You're really insecure. You fear rejection, so you think constantly about being accepted with a "most beautiful smile." You just don't want to seem insecure, so you ensnare your hormones and act like nothing is wrong with you. So get out of the dark and enjoy those "spring's sweet breezes" and falling petals, man.
Such is the curse of the romantic, my friend. If it truly is not the girl who is at the center of it, then it's fueled by feeling for her. The girl, no, woman, is far more than a metaphor. I'll admit that perhaps some of the underlying feelng is fear of her no having the same feelings for me that I have of her. When I'm with her, I feel like anything is attainable, if only for her sake. Perhaps it'd be considered naive, but after all, as Shakespeare said:
"O, how this spring of love resembleth
The uncertain glory of an April day;
Which now shows all the beauty of the sun,
And by and by a cloud takes all away."