Is it possible to break a guy up from his girlfriend?

my boyfriend just broke up with me and got back with his ex. he says although he likes me theres he just feels like she is the one (proably cause they have done everything to one another) but is ther anyway to break them upand get him back ? right nowwe are just like really really good friends just incase it doesn't wok out with her he can get me back but how can i convince him to take me back or break up with her ?