I'm so sorry to hear that, you know I actually had a very similar experience!
I loved a girl who was twenty years old when I was only fifteen, the trouble was that of course we could never be together...it made me incredibly depressed. To cut a very long story short somehow we did end up together, as bizzare as that sounds...but you'll quickly discover that it will never work. Reality will hit home and you'll go: shit, what was I thinking?
People can have successful relationships a world apart but I'd say it would have to be a very severely imbalanced affair. And with you being the female benefactor you will more than likely end up being used.
Sorry to break it down in such evil terms but the world is evil and love is the root from which it stems. You will be free when you can come to terms with loving yourself. I know I was.