Well sex always speeds up that process. You should sleep with your ex and then he will realize what he is missing and will want you back.
Just play it out as if you really could care less then he'll realize that he wants you back :)
Maybe that they have recently thought about you, and wanted to catch up. Or realize that they still has feelings for you and wants to try and get back together.
He probably wants to get back together in his heart but doesn't realize it yet or he wants to get back together but he doesn't want to come on too strong.
Just be strong. Move on without him because soon he will realize how much he needs you so for now act like you don't care. And when he asks for another chance, tell him how you felt the whole time he rejected you, and that next time he needs to realize he doesn't know how good he's got it, to have you.
The way to tell if your ex wants to work it out is to listen to her and watch her body language. Most woman are not subtle with how they feel about someone.
i would sabatage the ex to win him over.
He says, "I want you back."
If he's still calling ..
she wants to get back with him
If she was real, she will not become an ex.
Possibly that you ex misses you and wants to get back together
by asking him/her if he/she still wants you back or change a little bit and see if he/she wants to get back together with you or ask him/her if you want to get back together