for someone terrible like him?
there are so many interesting things they could've done with that concept instead of scrapping it mid-season and bringing it up once during the trials...
think about the potential it could've had. sam did feel bad for all the things he did when he was soulless. when he was given his memories back (both from the time he spent in the cage with lucifer and the time he spent whole being soulless),
what if he was plagued by these memories at the same time as he was hallucinating lucifer? what if he believed that he DESERVED being haunted by lucifer as punishment for being a bad person. what's more poetic than being tormented by the literal biblical devil
the thing abt a lot of people who don't think dean is abusive is that if you keep pushing at their logic and/or go deep enough into their posts eventually you will (almost no matter what) encounter the belief that dean's physical violence is at least mostly sam's fault