I was excited to wear my new dress. It was slimming, I thought: all black and covered with flounces from the neckline to the hemline. I wore it with high heels—which I rarely wear—and red drop earrings. I was feeling much more sophisticated than I usually do when I went over to my sister’s house for dinner. “Nice dress!” my mother said. I gave my new dress a little twirl and set the ruffles…