Should I ask her or not?

Here is the situation, I went on a blind date with this girl at college last spring. The date went well but the next day she told me she just say us as friends at the moment. "At the moment" was confusing me because then we started hanging out a little bit talking for hours and going to some club meetings together. I figured maybe she was interested in me but we went on our date a couple weeks before summer break. So some good friends of mine are getting married 9/10/11 and I'm thinking about asking this girl to go with me. I suppose if she agrees to go but just as friends then I should take that as a sign she doesn't want to be anything other than friends. Any insight on this issue? Thanks ahead of time!