https://www.royalroad.com/fiction/33726/first-contact

First Contact by Ralts Bloodthorne (no relation)

Eight Thousand Years after the Glassing of Earth, Terran Descent Humanity has largely become a post-scarcity society based on consent and enjoying life. With the discovery of another ancient race beyond the "Great Gulf", events and history collide to draw the Terran Confederacy into war against a hundred million year old empire that has always won and believes it always will. With allies and enemies of multiple species, the Orion Galactic Arm Spur will be wracked by warfare the likes of which have not been seen. Cracked, harried, wounded, and damaged, Terran Descent Humanity willfully throws itself against the universe itself.

"The universe hates you and will take away everything you love, laughing while it does so." - Terran belief.