I read a Fic awhile back that was set during Mystery Spot. It was from Sam's p.o.v. It followed the episode for a bit. Dean dying every day and Sam unable to save him no matter what he does.

After innumerable Tuesdays, Sam finally broke. Sam started getting drunk every day. One Tuesday, Sam ignored Dean, left motel to go to the convenience store bought (or maybe stole) a lot of alcohol, brought it back to the motel, and just started gulping it down as fast as he could. Dean freaked because he could tell something was really wrong with Sam but he couldn't get Sam to talk to him. Dean sat down and matched Sam shot for shot until he died of alcohol poisoning. I can't remember what happens after that but I think there was a happy ( or at least hopeful) ending. I looked through all the entries tagged with "Mystery Spot" on here and it isn't any of those.

Hopefully someone recognizes this Fic.

Found: Sometimes You Need a Few Drinks by flawedamythyst