when you open your eyes in the dark and you're about to go where there is light (i.e. when you wake up in the middle of the night to take a piss), keep an eye closed when youre in the lighted area. When youre back in the darkness, youll see that the eye you closed has retained its ability to see in the dark = no more bumping into random furniture and shit.
bonus culture points : thats why a lot of pirates are pictured wearing eye patches. NOT because they lost an eye, but because they kept an eye in the dark so they could quickly see in the darkness of the inside of the boat when they had to go get shit in there.