how will you react when your girlfriend teases you about your ex girl friend

Well, I know that when I tease my husband about his ex-girlfriend, it's all in good fun. It's a little mean, and I stop when he's getting annoyed, but there's some funny stuff about her. He teases me about my ex too. Just do it back. Tell her that her ex had an underbite or really long nose hair. If she gets upset, tell her that that's how it makes you feel also. Tell her you know that she's just joking but it's getting on your nerves. She may get mad at first, but she'll appreciate your honesty.