Tell him to go listen to Carol King. "it's too late Baby" why do people think they can end it & then change their mind. I have a rule "no take backs" life's too short to give them a second chance to screw up again. Start anew & start over when your ready & leave the loser in the past. Sometimes they do you a favor by dumping you.
This has happened to me too. I think it's cause he wants to get back with you but it's your choice, I wouldn't get with him if he broke up with you for another girl. But if he realizes that you're the only love he wants I would take it. But it's your choice. :)