I'm very glad I saved reading this one until the end--this is brilliant in every way. I think avidrosette said eloquently everything I was thinking while reading, except for this one part:

“I think you understand why I can’t be the first to say it after what’s happened.”

“Daniel!” Jack stared at him, helpless and horrified.

I was totally with Jack here--a perfect gut-punch of a line from Daniel, because he's saying it without saying it, just like Jack does with his name later.