He had decided a long time ago that he would never tell anyone, especially Sam, about the guilt that ate him up inside. It was always there. Some days it festered inside him, alive and well in the pit of his stomach. Other days, the good days, he didn't think much of it and just accepted it as another adorable quirk of Dean Winchester. There were never any good days anymore.

The solution came to him one day. He had had too much to drink and as he stumbled drunkenly back into the motel room; he realized that he didn't hate himself so much as usual. The alcohol numbed him, like a narcotic drug.

And so that's how he began to drink away his guilt, which was no longer festering like a fungus in his belly, but more like pneumonia, filling him up with guilt leaving no room for forgiveness.

He knew that Sam worried about him ("You're just a step away from alcoholism, Dean."), but Dean knew that Sam could not begin to understand the self loathing inside of him. There were years and years of failures just piled up inside of him like building blocks just waiting to spill over and break him, but God, the alcohol made it a little bit easier to deal with it. The alcohol gave the building blocks a stable foundation, making it possible to pile more shit on top of it.

And so, that's why he continued to drink even under the concerned gaze of his brother.

And so, that's why he continued to get up in the morning, ready to fight another day.