"Full darkness" isn't even a real thing in nature. It's hard to tell with light pollution, but even in the absolute middle of nowhere with no artificial lights, you're going to be able to see fairly well. Even with no moon, starlight isn't just an expression. And on a full moon it can be surprisingly "bright" if you're just out there for a while.
It's not like climbing into a cupboard, shutting the door, and sealing all the cracks with duct tape.
You may be used to needi g full darkness to sleep, but that's a learned habit. I guarantee if there was nothing you could do, it wouldn't take you long to adapt your "requirement" of total darkness.