"Dean, don't do this!"
"I was meant to be a demon, Sammy. Ever since I was born, my whole life has been leading to this. Selling my soul, hell, purgatory, killing the yellow-eyed demon, killing Dick Roman, killing all of them. All of those monsters we fought, Sam. Even mom. I know, I can see now...I was meant to love her and then lose her and dad-"
"and I didn't lose them too!?-"
"It's not the same, Sammy. I watched mom die and I couldn't stop it-"
"You were just a kid!-"
"and then Dad, he gave his life for mine. He went to hell and back for me-"
"What did you expect him to do?"
"I had to lie to you when we were kids and it tore me apart...and then I carried on lying, Sammy. I'm a drunk, I'm a murderer, I bottle things up. I turn against you, I turn against Cas. I mean, it's perfect demon material!-"
"Don't say that.-"
"Tell me I'm wrong..."
"...You're wrong."
"You never wondered why we couldn't be a normal family?-"
"Because of dad, because we're hunters!-"
"Because of me. I never let us be normal. I never let you be normal. All your life, I've been controlling you, I've been manipulating you-"
"No-"
"I never let you have freedom! I always had to have you right by my side!..and I never understood why...but now I know. It was because I needed to kill you."