I have this weird theory that when we die, time just speeds up from our perspective. When I die, all the things that come after death, all the millions of years, then the heat death of the universe will pass in a moment, since I won't be there to experience the passing of time. The question is what comes after, what is beyond infinity.
What we fail to understand is that there are things that we cannot understand. And death is one of those things in my opinion. Our minds are limited, our imagination is limited.
Like when ants appear in my kitchen, they cannot understand that it is my kitchen, it is impossible for them. The same way, the world, the universe and whatever's beyond it can be way more complex than we'll ever be able to comprehend.
Having said all that, I still think it could just be the end of the movie when we die, it's lights out forever, and that's it. And we won't even know, because we won't be there anymore.