There is no why. The Universe has no inherent purpose or meaning. Nothing happens for any particular intentional reason. There was no plan. There is no plan. It can’t be absurd because absurd implies there is some way things are supposed to be like, but there isn’t a right, just or correct way for things to exists. Things aren’t random though, everything in the universe is intricately interrelated and everything affects everything else at some level on some minuscule way and what ends up happening is the result of a million million years of causal collision of particles and forces interacting.
The nice part of this all is that meaning and purpose can be anything you want it to be. They’re human concepts and thus humans can mold them freely. You only have one life, savor the bittersweet, elate on the joy, for it all will pass. We are just the accumulative force of carbon combining in a futile attempt to stave off entropy, resulting in an data flow that makes the universe experience itself. And that I find to be wonderfully delightful.