If you find yourself taking life too seriously, consider this:
In a few hundred years, no one will know who you are. If you have children, and they have children, your name will be in a book somewhere in a basement with a few ancient-looking photos of you. Your grandchildren will remember your name, but your great-grandchildren won't, if they even ever hear it. Subsequent generations that carry a fraction of your genes before they're diluted beyond recognition won't even wonder about it, or if they do, it will be just in passing; a deep, anxiety-driven thought one might consider at 3 am, when people tend to think about things too vast for the human mind to truly understand. I wonder who my ancestors were three generations ago? Six? Ten? If a person born in 1950 looked back ten generations to see their ancestors, they would need access to documents from 1650, thirty years after English pilgrims landed at Plymouth, Massachusetts.
All of your accomplishments, the things you toiled so hard for, your unique and beautiful understanding of the world, your money, the skill you've built, everything will fade with you. If the words you wrote were published, like most things that are published, they will fade out of memory for most people within a few years. If you created things, they will rot beneath houses bulldozed long ago. In a couple hundred years, no one will know you ever existed.
After an immense stretch of time, assuming the human race doesn't die out sooner, the sun will destroy the earth and everything humans have created will be incinerated. We will likely all go extinct, and the rest of the universe, which is too big to imagine, will keep doing the things it has always been doing.
There are 200 billion galaxies in our observable universe and each galaxy contains hundreds of billions of stars. In our galaxy alone, there are an estimated 100 billion planets.
Consider this and feel small, the way you might feel when you look at where the horizon meets the ocean and try to consider the vast landscape of water on earth. Keep perspective. Nothing is as good or as bad as it seems. Nothing matters much at all, really. How very freeing that thought is.