On a recent night, a woman named Robin was asleep next to her husband, Steve, in their Brooklyn home, when her phone buzzed on the bedside table. Robin is in her mid-thirties with long, dirty-blond hair. She works as an interior designer, specializing in luxury homes. The couple had gone out to a natural-wine bar in Cobble Hill that evening, and had come home a few hours earlier and gone to bed. Their two young children were asleep in bedrooms down the hall. “I’m always, like, kind of one ear aw...