Dirty Martini Society

At what point does your ex become just a friend? After months of mentally expelling him from your life and thoughts you begin to think of the reasons that attracted you to him in the first place. The difference between him and the other guys you've been involved with was the fact that you two became friends before jumping into anything. So even though relationship has gone sour you still think about the positive qualities he had as a friend. Are these qualities enough to want a friendship post-breakup or should you keep him in the "never call again" discard pile? Furthermore is it even possible to have a platonic friendship after being so intimate?