That "mean thing" is definitely something that you don't want. I was gaming this chic at one point, with a very fragile ego i might add, my naturally sarcastic nature got me that "mean" title. I found out later she took every C+F & sarcastic comment (no matter what the subject was) as a personal attack directed towards her, which brought things to a halt quite quick.
You have to make a judgment call on when you think the C+F isn't having the desired effect and change the way you handle yourself, it's not what the comment was meant to convey, it's all about how it's received, and if the comments are not received in a manner which will provoke the desired effect, more is definitely not better. Try not to bust on her so much, but like speakeasy said, you have to be funny and flirtatious when being C+F, if she still thinks its mean, cut back a little more, but don't stop busting on her.