I desperately need your help?

I've liked this girl(Well more like a lady) for over five years�now. Honestly, words don't describe how amazing I think she is. Going up, and talking to any other girl wouldn't be that big of a deal for me. But around her I'm speechless. Never gathered up enuf �courage to go, and talk to her. High school is coming to the end for the both of us. I don't want to loss the�opportunity, if I stand idly by, and don't do anything I know I'm going to hate myself for a very long time. I would really appreciate anything that may help. Ways to raise my self-confidence, any recommendations, advice, ext. Would be�phenomenal. Thanks!