Earplugs have been a game changer for me in this department. As an extremely light sleeper I've been struggling all my life with other people snoring or even semi-loud breathing.

After I started using earplugs I'm now sleeping through the night even better than when I slept by myself. I feel like when I wear them I'm in an isolation chamber :)

The trick was finding earplugs that don't hurt after wearing them for 8 hours, but after having tried a few I landed on some acceptable ones (I can still feel them but they're not uncomfortable if inserted properly)