Jerry Seinfeld and Elaine Bennet did it on TV. It is possible in real life too. I think it depends on how the break up went.
There's this guy, and we were best friends for 6-7 months. We got into a relationship, but after some months we broke up after some misunderstanding. But as a friend, he's the best, losing a friend like him is one of the worst things that ever happened to me. Now what to do?
I think you should tell him how you feel. In fact, tell him that losing his friendship was the worst thing that ever happened to you. Who knows...maybe the relationship can be repaired.