Junior year I had a similar problem, I spent the better part of four months in the "quasi-dating" stage with one of my closer female friends, but in the end I just stopped trying to win her over and decided to just be friends. Tension was high during the dates anyway, and I fear if I pushed further I'd do something stupid(the first date was a total disaster) we'd never be on speaking terms again. We never really talked about it, and the whole thing sort of evaporated after prom, but we ended up good friends.
Just enjoy spending time with her and suck it up, its what I did and I got over it.