If your ex is a human. He will start feeling guilty for what he did. If he loved you sooner or later he will regret his decision. I’m not sure if it will be too late when he realizes it. Most of the times. Ex comes back way too late. When you don’t even want them near. Some people say that if he loved you he will realize sooner before you forget him. However the others will reappear later on.
I don’t hope for my ex to want me back, because Im not in it for another rejection. That causes more pain. It’s better to stay as friends. I’m protecting my heart. I finished sticking back the pieces he broke.