What I remember of this story is that the Apocalypse is over, Sam doesn't remember his part in it, Castiel is dead and Dean is the only human alive that remembers anything. It takes place in a church with Dean confessing to a priest, basically asking if there is a heaven for Angels. I'm pretty sure Uriel makes an appearance near the end and wipes the priest's mind as a form of punishment for Dean.

Any help would be greatly appreciated.