It is difficult to quantify many benefits of middle age. But every now and again a statistic comes along that may make the seven million American women aged 45-64 (US Census numbers, not my definition of middle age) who live alone count their blessings. According to a recent study single men wash their bed sheets four times a year. (Single women wash them every two weeks.) Though this averages out to once every three months, you just know that there are periods of determination, perhaps following a New Year’s resolution, during which the frequency is nearly civilized–which means that the situation in the intervals that follow is truly crusty.