Most Helpful Girl
Do you still have contact with her? Does your ex still contact you? If so that is the biggest indication to a woman you are not over your ex. If you don't and she is still set in the fact that you still have feeling for your ex ask her why she feels that way. My experience is, if you haven't given them a reason to think so it is their issue and you won't be able to change their mind. Sorry bud.
Most Helpful Guy
Honestly dude I doubt ANYTHING you do will make her think otherwise, she's obviously very insecure. How Long have you and the ex been broken up? How long have you been with your current girlfriend?