I have strong feelings for a girl that hates me. How should I stop having them?

There is this girl at work and she looks amazing. Every time I am with her at work, she always telling me off and bossing me around. She is often rather mean to me, in a way that hurts my heart. The fact that she made me cry the other week, is what prompted me to post this question, that and she is under 18 and has a boyfriend. I don't cry very often, I've only cried once since high school, which is another reason why this situation is rather distressing to me. I have been thinking about her everyday since that day. I suppose the reason that I've always been infatuated with her, is that at times she can be one of the nicest, most charming people that I know. Her voice is one of the sweetest ones I have ever heard, a voice that sounds of abundant warmth and care. She just doesn't care for me, I think it may be because she has tried to connect with me in the past, but with me being a very introverted person, I didn't exactly meet her halfway, plus I have really pissed her off a few times. I think she just mean to me because fairly often I can be a real prick.