My girlfriend of 8 months just broke up with me, what should I do?

My girlfriend of 8 months just broke up with me, what should I do?
Hi, I'm a 17 year old guy, and my girlfriend for 8 months just broke up with me because she felt she could'nt carry on with our long-distance relationship. She broke up a couple days ago. She lives an hour away from me and we met up on every weekend. She says that she does'nt love me enough to carry on. I analysed that the reason that she broke up with me is because I was getting on her nerves too often and causing silly arguments.
I know a lot will say that I should 'let her go, plenty more fish in the sea blah blah...' but she means so much to me.. I trully regret all the arguments, and I'd do anything to get her back.
The bad thing is- I've been through all the text message-terrorism stage for about 5 days, but then i finally let her go. We're still texting, a she says she wants to be friends. For the time being, I'm hiding my feelings and appear that I've gotten over her already... I'm not sure what should I do- should I text her as a friend or not? I'm afraid that she'll get to used to the fact that we were destined to be just friends.
I am guaranteed to see her at a concert next week. What should I do? should i confront her a tell her i still have feelings for her?...or not?
thanks.