the island was real. the oceanic flight 815 survivors were the ones who, for the first time in two thousand years, were able to reverse the endless pattern of people who came to the island. they did not kill each other. they were not in it for only themselves. in the end, they simply sacrificed for each other.
got that? the island was a test. they passed.
that being said, the flash-sideways wasn't purgatory. it was an alternate world. and i feel like it's one that was created by hurley as a thank you to jack for sacrificing himself. think about it. he's really the only one who had good things happen to him. everything worked out for him. he became the father figure he never had. he successfully fixed a dursa sac operation. he met the stepsister he never knew he had. he had a great relationship with his ex-wife. nothing's perfect, but for jack, this was close.
where am i going with this? in the sideways world, all the other oceanic 815 survivors were just props. they exist to meet jack in the afterlife. those moments of connection, where they realize that they knew each other, that signaled the revelation that the afterlife was waiting for them, and this was the person and people they want to spend it with. this was enlightenment, one that happened at different moments to each of them, and jack was the last one to get it.
and the ending?
they each continued to live their lives in stories we weren't told. they just happened. then, at some point, they left this earth and prepared to move on to the light, the afterlife...but they didn't. they decided to wait.
because, at that point, time became irrelevant.
christian shephard said something important to jack, and i'm paraphrasing, "some died before you and some died after". hurley told ben that he was a "great number two". their lives were lived. their redemptions were had. and in the end, they passed. and time didn't matter anymore.
but you know what does matter? going to the light with all those who you care for the most.
and for these people who were broken and lonely beforehand, what ultimately mattered the most to them, in any life they led, was that time they spent with each other on the island. that's what made those "connections" they had so electric. we've all had them with the most important people in our lives, the feeling that even though we've just met them, we've known them forever. in whatever life they lived, that time they spent together on the island redeemed themselves.
yes, the island was a test. but it was also a bond.
they might have died alone, but together, they will live forever.
and they were just waiting for jack.
or maybe i'm completely full of shit.