I have been in the same situation that you have been, My mother use to always tell me not to "chase" a guy. Makes you look desprate and it turns guys off. My advice to you is, and I know i might sound nuts. But pretend you have moved on. Guys want what they can't have. If he sees you smiling and being happy, and showing that you really don't care that you guys broke up, than it's going to make him stop and think....Another is give him time. I hope this helps you out.
Amye
http://www.noir-ailes.com/amye