How you view death impacts how you live life. You now have a feeling shared and contemplated by all of humankind before you, and all the humankind after you. This is the human condition.
Embrace it, come to terms with it, choose to live today and enjoy rather than worrying about that which you have no control over.
Those words are very easy to type but much harder to live.
What about counting the probable number of years you have left, and from there the number of things you have time to do? How may meals, movies, vacations left? Can you waste this rest day eating ramen in front of a bad Netflix show?
Have fun
This is a real phenomenon. The way it was explained to me, it's because of how time takes a relatively smaller percentage of your lifespan when you're older. When you're ten, 5 years represents half your life, so 5 years feels like it passes very slowly; when you're 50, 5 years represents 10% of your life, so 5 years feels like it goes by in an instant.
Me too. There is a lot of evidence for it that doesn't have religion tied to it if you look hard enough. But it's one of those things you'd have to have direct experience with to believe it.