On the witness stand, Jack says that he loved Kate once, but no longer. Then in the garage he tells her it was a lie...meaning he does love her. Why does her eyes light up like that? I thought she really loved Sawyer? (Which is why I was expecting the baby to be Sawyer's.)
Anyway, I don't think the other survivors left on the island are dead. Why would Hurley be "seeing" Charlie and getting prompted to go help them? He is definitely too scared to go back. Kate doesn't want to go back (could be because of the probation we just learned about?) but Jack feels guilty and wants to fix things somehow. I think Claire couldn't leave for some reason, she asks Kate to take Aaron to keep him safe, and Jack goes along with the story. Because if Kate had done something to Claire to get off the island I don't think Jack would be telling her that he still loved her in the garage.
I don't think Aaron counts as one of the Oceanic 6 as he wasn't one of the original passengers. (The timeline still screws me up.)