Hi jefferaldo,
I think you made the right decision, and it's great that a person your age has the foresight to put your education first. There is just one thing I would add. You say there is a mutual attraction between you and this girl. Have you told her why you turned her down? From your post it sounds like you just kind of turned her down without explanation. If you like her and want to pursue a friendship, explain to her what you put in your post. She should understand, but if she doesn't, then you know she's not for you. You can have a relationship so long as it doesn't interfere with school.
Can you invite her to watch orchestra practice? That might be fun for both of you, and then you could go out afterward. It would show her that you are committed to your studies, and include her in something important to you.
Hope this helps.
