All I can say is don't be hard on yourself. I know how it feels, when I used to go to my classes on my first day each semester, we'd do the stupid activity where everyone says their name and something about themselves, I always looked like an idiot when it took me a full minute to say my name. You have to let it go and realize that people won't care or even remember the next day. Finally I want to point out one thing - the biggest assholes I've ever met in my life were the ones that were similar to those girls. At least look at it in a sense where you can tell which people are truly good by the way they react to you stuttering.