“Pretty girls don't buy cocaine,” Greta1 says and laughs as she walks out the front door.My hands and face sting as I stand frozen in the entryway and hear her start the car. I'd asked my twenty-two-year-old daughter where she got the money to feed the addictions she was battling.Over the past three years, she'd chosen a few subpar boyfriends who introduced her to substances, which helped set...