I will say the one part of this episode that I really loved is that it was revealed that the mark isn’t just a curse. The bearer of the mark actively holds back the darkness that existed before creation, the darkness so destructive that God and his angels had to insure it would be locked away for all eternity, and Dean was strong enough to fight that and still remain mostly good through all of it. Even with all of the bad he did, his number one concern was still protecting innocents. He still put saving people above all else.
Dean Winchester is so brave and so strong and I am so, so proud of him.