Craig LeMoult

Nearly 1.5 million Americans were treated for addiction to prescription opioids or heroin in 2015, according to federal estimates, and when those people get seriously hurt or need surgery, it's often not clear, even to many doctors, how to safely manage their pain. For some former addicts, what begins as pain relief ends in tragedy.

Nicole Hockley says she used to be the kind of person who knew where she was going in life. Then, last Dec. 14, her 6-year-old son, Dylan, was one of the 26 victims killed by a gunman at Sandy Hook Elementary.

"Every plan I had went out the window, and I just kind of lost my way in terms of where do you go from here, how do you pick yourself up and move forward and find a new path," Hockley says.

The phone kept ringing at home, and media outlets sent flowers with cards asking for interviews.