I was thinking about how Christian said that the Losties created the place where they were to meet, and then I wondered if perhaps each person created their own world based on their hopes or thoughts about themselves. For example:
Sayid created a world where he couldn't have Nadia because he felt he was unworthy of having her.
Sawyer made himself a cop because he believed that he could be the hero and look out for others before himself
In Kate's world she was innocent but she still had to run because she still wasn't ready to face the pain of leaving Jack behind.
Jack's world was one where he got to be a better father than the one he was given...to prove that he could do it.
John created a world where he got revenge on the father who paralyzed him (by making him crazy) but still got to have that relationship with him. He also got to have the happily ever after with Helen that he missed in real life.
Jin and Sun were in a world in which they still loved each other, but obstacles stood in their way...maybe to show that their love could withstand anything.
Claire got to start over with Aaron and be the mother she wanted to be.
Charlie created a world in which he was still a drug addict, but he knew he was missing something...he gave himself hope that he could change.
I'm sure I'm missing someone, but what do you think?