Jacks father said, "ever that happened was real. the time you spend with these people was the most important part of your life".
This season, 'sideways flash' was more of a ultimate flashforward.! Everything that happened on the island was real, people died, people lived, different people came and went and/or tryedto take over the island.
In the end the island was taken care of. the MIB was dead. So evil was not going to leave the island. The island itselfwas not have evil, The MIB was evil and should'nt leave the island. Jacob had someone to look after the island, Hurly, with Ben's help.. And when it was their time to die Hurly and Ben died.. Remember Hurly said to Ben sitting outside the church. "you were a good second," and ben said to Hurly, "you were a good number one" This says they lived and most likely died on the island.
The people in my idea of the ultimate flashforward did NOT die all together or all at one time. Charlie died when he drowned, Boone did from having the plan fall on him, Jin and Sun died in the Sub.. and so on.. This 'flashforward' was them all getting together, when they 'all found each other when they needed to or when they were ready.
the people that flew off in the plane the last time. Frank and Kate and Sawyer and Clair and miles, lived... in another lost world we find out what happened to them, did Kate and Sawyer have a life together, did Miles still have Nikki and Paulo diamonds and how did they explain how Claire was still alive.? But we won't.. we have to live with that open ending.. Even in the real real world we don't always have an ending.
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