Not sure if this is what you're looking for. Basically it's Dean's journey during the time Sam was at Stanford. He sinks pretty low, and he pulls himself back up. The link is to the first part of the story, and it's a long one. It's one of the first stories I read in the fandom, and I'm still re-reading it 7 years later.

http://sites.google.com/site/stele3/the1300dayspart1

Hope you enjoy!