I think easily the most poignant thing about this entire conversation was Cas asking for reassurance from Sam that Dean would still possibly be Dean somehow. I guess it could be argued that Cas was in bed because he’s sick and dying, but this scene reads to me as a man who’s sick with worry more than anything. Pining for his lost love, and hoping for a miracle.
It sounds to me like he had been working with Sam to find Dean, but Sam pushed him away after he suffered his injury. So the image of Cas lying in bed waiting on word from Sam if he had found anything out? Absolutely heartbreaking. He could have been out helping Heaven after he was no longer with Sam I suppose, in fact he never really explained to Hannah why he didn’t go to Heaven and the angels sooner, but I have to assume the answer would be something like “I was searching for Dean, you know, the one I gave everything for. Then I came back to this motel room and laid around sadly waiting for word he was okay.”
Once Hannah showed up however, he seemed sort of resigned to his fate. Not only to death, but to life as an angel before his grace fizzles out for good. He needs hope that Dean is still alive somewhere, that he’s still himself, but after that conversation with Sam he has none it seems. Free will isn’t nearly as appealing when the one man he wanted to choose above all else is gone, without explanation, and there’s seemingly nothing he can do to find him.
