A candle burning out or growing?

Ok, well there's this girl who's name is Brandy. She's a great girl who was even going to ask me out around the time i was going to ask her out. Sadly enough someone (or she thought) i went out with someone else at the time and things went downhill. instead of becoming friends we turned (well i became her enemy) rivals. I need advice on how to fix this so i could increase my chances of going out with her. And if u want more background information feel free to ask me.