Dean's been calling for hours when he realises that no one is coming, no one cares and he was wrong to wait this long to say yes.

He calls on Cas, not expecting him to come but the angel is there straight away holding him as he sobs because he feels worthless and broken. Cas holds him together and says the words he needs to hear.

He realises he doesn't need Michael to save the world, the three of them can do it themselves.