Some have likened the experience of death to what it's like when you black out (true loss of consciousness) or, to a lesser extent, when you go to sleep at night. One moment you're there, the next moment you're coming back from not being there. (Give me some leeway on the sleep thing - I know that when you're actively dreaming or tossing and turning it's not quite a jump cut).
So in that moment when you're coming back to consciousness from a state of previous unconsciousness, what's to say you're the same "you" that was beforehand? Sure, you remember a whole life, but then there's this gap in continuity. Maybe you were someone else and then all of a sudden, you're now "you" with all those memories in that mushy brain of yours.
But if that's the case, why is the gap of consciousness needed to separate "you"? What's to say that from any given instant to any other given instant the "you" is continuous, other than for this stream of memories coming from your meat brain. Maybe "you" jumps around all the time.
But then - what is "you" anyway? If we're just a collection of meat brain memories, maybe there's no core identifying "you" in the first place, and we're all just part of a big collective pool? Like a piece of code running in an overall shared memory space. The complexity forms (your program / you), and then the function exits and the memory goes back to the collective pool.
So then - what if life and existence is all about perspective? I'm me because, well, I'm me. I expeierience this life and remember these memories. And you're you because you experience your life and remember your memories. Is there really a difference from a third-party observer?
Maybe life is simply in the eye of the beholder. As long as there is ANY conscious life, then life is being experienced. And so maybe death really is nothing to worry about -- you'll get a chance to experience another life as someone else.
But then - why does it even need to be linear? Maybe we ARE experiencing life as someone else -- as evidenced by all the someone elses experiencing life right now :). Just because we can't experience it (hardware limitations - sorry. Brain can't handle multiple sets of inputs ;) doesn't mean it's not happening.
Maybe we're all experiencing consciousness in our own ways as part of one big system. That leopard in the zoo is experiencing it. I'm experiencing it. You reading this are experiencing it. Maybe our meat brains and linear single-track memories are just a nice little lie, and we're really just all temporary functions running as part of a bigger computing system. Function runs, exits, memory goes back to the shared pool. New function runs, exits, memory goes back to the shared pool. Many functions run simultaneously - each doing only what it was programmed to do, then each exits and the memory gets released again....
This really gets wild when you start thinking about clone experiments (or teleportation). Make a perfect clone of yourself right now, down to the neuron, and assemble it in across the room. You'll experience nothing other than to see a clone appear 10 feet away from you. Your clone will have the experience of being you one instant, and then waking up across the room looking at you "Holy cow! Cloning and teleportation worked! They're real!" Then your clone will go on with life, doing the same things you want to do, remembering the same things you remember.
Then think about whether there's REALLY any difference between that clone of you and any other person on earth....