Bobby Azarian, Science Journalist at the Atlantic, talks about the existential fear of forever (Made into a more compact video above, but I personally like the article):
Woody Allen once said, “Eternity is a very long time, especially toward the end!” Eternity sounds great on the surface, but actually experiencing it may be an entirely different matter. For some people, the very notion of infinity sends chills up the spine. In fact, for many who suffer from “apeirophobia”—a term for the fear of eternity—the thought of an existence that goes on forever amounts to torture.
Not only is eternity an existential terror, but it would also be depressing. For as much of an ultraviolent gore-fest as the Hellsing series is, it gets into the idea of this. Alucard is depressed at the immortal monster he has become, and regrets his choice immensely. Every time I nearly fear death, I think of Alucard and then infinite nothingness doesn’t seem so bad.
I personally believe the best solution to this is made by my favourite existential comedy, Rick and Morty: Don’t think about it.