Dwyer finally found what he needed at a VA-run substance-abuse program on Long Island, where he spent eight months with soldiers like him. He devoted hours every day to therapy, willingly confronting, for the first time, what he'd seen and done in Iraq. On the phone with Matina, he finally confessed to the thing he could not get past, the one moment of the war that forever changed him. Not the heroic moment. Something else. Near the end of his tour, his unit was assigned to search for Saddam and his criminal cohorts. On a dark night during a raid, Dwyer burst into a house, kicked open a door, and saw someone rush toward him. He fired his gun. Then he looked to see who he'd killed: an unarmed woman. In front of her young child. "I killed a lady, a mother," he told Matina. "I don't understand how I could become someone who would do that, just . . . kill . . . like an animal. How can God forgive that? How?"

He returned home on March 1, 2008. Six days later, Matina found him in the computer room, huffing. She turned around, picked up Meagan, and walked out. Alone, Dwyer spiraled. He had bored a hole through a closet wall to make a bunker, and he took to hiding in it with a gun when he felt threatened. Every morning, he called a taxi to drive him to a computer store, where he bought a supply of Dust-Off. On the night of June 28, he called a taxi to take him to the hospital. When the driver arrived at his house, Dwyer shouted that he couldn't get up. The police arrived a few minutes later and broke down the door. They found him on the floor, lying in his own feces, surrounded by empty cans of Dust-Off. "Help me, please," Dwyer groaned. "I'm dying. . . . I can't breathe." As the paramedics rolled him to the ambulance, he took his last breath. Five years after surviving war, Dwyer had huffed himself to death.

The famous soldier from those first heroic days of the war was suddenly news again. On the website legacy.com, hundreds of strangers wrote tributes to him, some with prayers—pleas—for his death to resonate, to keep others from suffering as he did. Mt. Sinai, Dwyer's Long Island hometown, named a street after him; a family friend formed a nonprofit in his name to raise money for disabled vets. Dwyer was no longer just one American soldier suffering from PTSD; he was, again, a symbol—but this time, a symbol of how we treat our heroes. "There should have been more help here for Joseph," Matina says. "He was all alone and felt like nothing could help him, like nothing had worked. He never really came home at all."