I think I know what you mean. I loved the episode, and my head is spinning, but I'm not as emotional as I expected to be. I can feel it all boiling in the background though, so I keep myself busy with thinking about it and writing a proper review.
Sam has always been more forgiving than Dean. Forgiving Cas like he did is big, but I do think that it is also consistent with his character.
I'm pretty pissed with Dean, to be honest.