@TNT -Dean’s father makes a deal with Azazel in order to keep him alive but Dean is approached by a reaper who Dean believes will guide him in the right direction.
Wincest!
Well, story is simple.
Sam found out that Dean is unfaithful to him. He broke up but Dean did not want to let him go and so he had to live with the consequences and the fact that Sam never will be his lover again...