Was taking a girl to a formal dance and we planned on going together, the two of us. So I made plans, reservations, etc, and I get an email a few days later from her saying she changed her mind and that she wanted us to go with her friends.
An AFC would have said, "Ok, sure, whatever you say."
However, I said, "Haha, you're such a waffler. You afraid to take me one to one? If you're friends want to come with us, they can, otherwise, I'm picking you up at 7:00. Be sure to email me your address."
Her reply was, "Wow. Well, I'm glad you're being assertive. yadda yadda yadda..."
Just be sure to relax, be unreactive, ignore them, give it back to 'em, call 'em on it, refuse to play games, refuse to tolerate manipulative behaviour. Be confident, cool, yet sometimes you'll need to be on your toes.