The Flashsideways reminds me a lot of a dimension called The Fade in the game.
It's a false world that you forget the world you're really from and you are either in constant torment or at peace in this world but none of it's real. You're really in that dimension where a demon is feeding off of your mind so it can exist in the real world. It takes other members of your party to travel into The Fade and find the other members to restore their memories and unmask the shame of that dimension. Kind of like when LOST members make contact with other certain members they regain their memory.
Only difference in LOST is instead of moving on to a new place you wake up in your former existence and fall back on your original journey.
Anyway, just wondering if anyone played it and saw the comparison.