Dana told me Riley's father was a recovered gambling addict. I did not know this. In two and a half years, Riley had never mentioned it. He'd gone dry when she was twelve. Had attended Gamblers Anonymous for eight years. Had, Dana said, told Riley once — just once, when she was seventeen and about to leave for college — that she needed to be careful because the thing that lived in him might live in her too. Riley, Dana said, had laughed it off. Told her father she wasn't like him. But apparently, somewhere between our first date and that last Tuesday, something had cracked open inside my girlfriend and the thing her father warned her about had climbed out. Dana cried on the phone. Then she asked me the hardest question anyone has ever asked me. She asked me, gently, whether I loved Riley enough to stay and help her — or whether I was calling because I already knew I was leaving. I didn't answer Dana. But by the end of that week, I had an answer for myself.