Amanda Eleazer remembers when she started using drugs. It was 2014, and she was a 25-year-old mother of four living in Tennessee. Her husband was a patient at a local pain clinic, which she now realizes was a “pill mill,” a facility that illegally prescribes opioid painkillers such as oxycodone. He would offer to share his pills with her, and at first Eleazer declined. But one day, she accepted —…