Gravity Between Us by Alexandra Norton

I thought I could walk away. I’ve done it many times. But all the roads lead back to her.

Elaina Fairan knows she’s broken. Maybe that’s why she’s been hiding at the edge of the universe, guarding herself with her work. Vulnerability has never been her strong suit, and machines are simpler than people. But when a magnetic Gaian stranger walks into her life, something about him makes her wonder if maybe she’s finally ready to stop running.
Cyan Orlogsson thought he was guided by fate itself when the ancient sword he bears pulled him to the edge of the known universe. He’s left behind everything—everyone—for this duty. He can’t let the aloof astrotechnician with striking eyes, or the electric connection between them, steer him off-course. But something about her makes him question everything he thought he knew about his purpose… Something about her feels like home.
As the fabric of their very universe unravels, Elaina and Cyan must risk everything—including their hearts—to stop the collapse. Can they find the courage to lean into a bond powerful enough to rewrite the stars? Or will their fear of falling tear them apart?

Gravity Between Us is a steamy sci-fi romance in which two fragile human souls must overcome their deepest fears—and fate itself—for a chance at love.