Supernatural, Season 4

Dean:
You did the right thing, you know. That guy was a monster, there was no going back. Sam, I wanna tell you I'm sorry. I've been kind of hard on you lately.

Sam:
Don't worry about it, Dean.

Dean:
It's just that your, uh, your psychic thing, it scares the crap out of me.

Sam:
Look, if it's all the same... I'd really rather not talk about it.

Dean:
Wait. What? You don't want to talk? You?

Sam:
There's nothing more to say. I can't keep explaining myself to you. I can't make you understand.

Dean:
Why don't you try?

Sam:
I can't. Because this thing, this blood, it's not in you the way it's in me. It's just something I gotta deal with.

Dean:
Not alone.

Sam:
Anyway, it doesn't matter. These powers... it's playing with fire. I'm done with them. I'm done with everything.

Dean:
Really? Well, that's a relief. Thank you.

Sam:
Don't thank me. I'm not doing it for you. Or for the angels or for anybody. This is my choice.