One of the things that has helped me get into and maintain the state of 'grasping the concept of death' is the idea of the universe existing (for billions of years) prior to my awakening to conscious existence, and returning to that state of dis-being; non-existing.

I also figure: you have only known existence. You will never know non-existence. You can sleep deeply for hours and it feels like a mere moment. For all you know, there is only existence. This is my backdoor way of getting to reincarnation.

Infinite time and universes might pass, but if you were ever conscious, why would it be impossible? Thinking people lack proper logic and perspective, but it's not even about belief systems, or even identity.