I'm going to join you on this one, the ending to 358/2 is just tragic and despite knowing it wasn't going to end well, it still found a way to sucker punch you pretty badly.

Course the ending to BBS is no slouch either, KH must have a large list of Doomed by Canon on TV Tropes. The ending to KH1 and Sora's story in CoM were certainly bittersweet as well. Maybe this is why I couldn't get behind KH2, it broke tradition and gave us a fairy tale ending, after two games before it gave you the finger, and the two games after tore your heart out and stomped on it.