They became the people the feared the most....

Jack became the drunk/drug addict...
Kate became the good girl...

Why would Kate fear being the good girl?
All her life shes tried to do the right thing - her intentions have always been good

she feared it because she couldnt become it....They both became their other selves....
'They went through the looking glass.....

In Alice the looking glass bring out the alter 'twin" of yourself..

The only thing I can figure about Jack's reaction to being home is whatever he witnessed when they got rescued haunts him. It looks like Ben might have been telling the truth on that one. Were the Others killed in front of our Losties? Is that what has effected Jack so badly?

I think Jack has been living a lie claiming he never was on flight 815 or something to that effect. :shrug:

I think Jack has been living a lie claiming he never was on flight 815 or something to that effect. :shrug:

No, They got Gold Passes from the Airlines that let the fly free to wherever they want. Something was wrong with the entire flash forward. His dad was still alive. I think we're talking alternate timelines.

On another note, The "he" that Kate was talking about could be that federal agent that has been on her case. Keeping a close eye on her now that she's back.

I think that's a pretty interesting observation, minnie. Jack takes on the problems of his father. Kate seems to worry about Him wondering where she is, as if Kate is tied down in a relationship. Taco nights redux for the gal who was born to run. I'm not sure there's anything to this, but it's a pretty astute observation.

Charlie became the brave guy who saves things, rather than the druggie who wrecks things.

And LOST is about redemption.

When Kate made the "he'll start wondering where I am" comment it sounded to me like she was talking about someone very possesive or jealous. If Jack has turned into a drugged out drunk like his father then maybe Kate is now in an abusive relationship with someone like her father.

From Wikipedia on Lewis Carroll's "Through the Looking-Glass, and What Alice Found There":
In it, there are many mirror themes, including opposites, time running backwards, and so on.

They became the people the feared the most....

Jack became the drunk/drug addict...
Kate became the good girl...

What I found incredibly interesting about the flash-forward was Jacks obsession with the island and getting back to it. It seems to me that the Losties are all people that have done bad things in their lives;they all have regrets and made the wrong choices at one point or another. But I think the most important thing is that they don't really serve a purpose off the island, they seem to be lost themselves. Jacks obsessed with fixing everyone and everything. His personality forces him to believe that he can always have his cake and eat it too. Kate made many mistakes and is plagued by them constantly, always on the run. Her dream of settling down and having a family is frightening because she is plagued with her past. Locke is a person who always seemed to be floating around in life looking for a purpose. He never fit in anywhere and was constantly plagued by his memories of what his con-father did to him. The island seems to offer people a purpose and a chance for redemption, a chance to start over;it is something that is not offered anywhere else.

I used to believe that this redemption was offered with a chance to leave the island. I now am not so sure and in response to your thread Minnie, yes it is quite possible that they might end up a product of their experiences if they were to leave the island. Jack might indeed follow in his fathers footsteps, a family who solves their problems by supplementing their issues with instant mental quickfixes like alcohol and drugs. Kate might indeed end up in an abusive relationship like her mother. I think this whole series is a great commentary on not only the nature vs nurture debate, but the power that our parents have to influence our life choices. This also goes hand in hand with the resistance to change; it is very hard for a tiger to truly change its stripes, but it's possible.

they must become something (or someone) other than what Fate has written.

I'm liking the alternate timeline idea. If that is the case, wouldn't it be cool if the "he" Kate refers to is the marshall? Maybe that's why there seemed to be so much between them in their current timeline.

I think what we saw in the flashforward is the lives of Kate and Jack with the one thing they each regretted most undone. Kate regretted killing her father because her motivation in doing so was to bring her closer to her mother. Instead, the opposite happened. Jack regretted ratting on his father's drinking because it ultimately led him to run away to Australia to drink himself to death. I don't know how else to explain Kate being free and Jack commenting about his father as if he was alive.

regret definitely seems to be a factor.

Ben would always be telling the truth, and never try to manipulate anybody. James Ford would be a loveable oaf who's goal is to please everybody. Locke would settle down with Helen and become a stay at home dad. Hurley would become an oil tycoon and buy up Paik-Hanso-Dharma-Widmore.

Oh, and the redshirts on the show would take one big step forward and we would find out more about them. :)
Also, all dead characters on Lost would become alive again.