I think she made a choice, and it was Sawyer. That said she can still feel strongly about not leaving Jack behind. As for Jack he did agree to do the surgery and in doing so saving Sawyers life. That's all the info Kate gave him. do it or he dies. He could have saw the two of them together and said fine they can have one another I just want off this island.

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Hope is a very dangerous thing to lose. - Sayid

I do what my Rice Krispies tell me to. - Anonymous