Supernatural, Season 4

Dean:
You were right. I shouldn't have lied to you. I do remember everything that happened to me in the pit. Everything.

Sam:
So, tell me about it.

Dean:
No. I won't lie anymore, but I'm not going to talk about it.

Sam:
Dean, look, you can't just shoulder this thing alone. You gotta let me help.

Dean:
How? Do you really think that a little heart-to-heart, some sharing and caring, is gonna change anything? Hmm? Somehow... heal me? I'm not talking about a bad day here.

Sam:
I know that.

Dean:
The things that I saw... there aren't words. There is no forgetting. There's no making it better. Because it is right here... Forever. You wouldn't understand. And I could never make you understand. So I am sorry.