It's sad to know there is nothing after this existence as we know it. oh well
Not so fast. We are dead before born right. There was nothing before this existence, yet here you are.
What if sooner or later those same particles of energy that constitutes you now, are recombined by chance again, in a biological fashion. Let's say after X amount of universe cycles you are up and ruining again as something else or even same (by ultra rare chance). The time in between is non consciousness so you basically be reborn as soon as you die.
So it be more scary if it NEVER fucking STOPS. No rest, no respite, FOREVER.