On the night of Aug. 15, 2014, Zoë Quinn was out having a drink with some friends in San Francisco when her phone began to blow up with messages. Something was exploding on the internet — a strange, incoherent maelstrom of outrage that would take over her life. Ms. Quinn, a 27-year-old video game developer, lived in Boston and was in San Francisco only to visit, but the visit turned into exile.

“I never went home from San Francisco,” she told me.