My daughter is 35 now but I went through this same sort of stuff with her. She could not understand how this sort of thing could lead to worse things until she came home pregnant. NOT because I let her go to any of these parties but she would sneak out and meet up with her so-called-friends or even better yet "stay late at school" so she could run around with her friends. She did married the father but after 14 years of him cheating on her then her cheating on him out of spite, she'd had enough and this past summer they have now split up. She has 2 girls ages 14 and 8 and they have watch how their parents has treated each other all these years. It's heart breaking to see how they have become so un-trusting towards people. Maybe you can share this story with your daughter and maybe it will help her to understand how things can go so bad when they seem so innocent.