What if you explained that she's a good friend and everyone is drunk and driving and you're really worried about her?
It's worth a shot.
Or you could sneak out and steal your parent's car...
One of my co-workers (I actually went to school with him too) got CRAZY messed up last weekend. It was someone's 18th birthday and there was mad drinking. He got so drunk that he had no idea where he was and who his friend were. He almost died. He's fine now, but he definitely learned his lesson.