Tomas Young, the Iraq war veteran who was injured in combat and came home to become one of the most vocal critics of the war, died on Monday at age 34. Army veteran Young was shot by an Iraqi sniper's bullet and paralyzed from the chest down in April 2004 while riding in an unarmored Humvee after serving in Iraq for less than a week. He passed less than 24 hours before Veterans Day, when a reported 800,000 people crowded onto the National Mall on Tuesday for the first-ever "Concert for Valor" in honor of veterans.

Young died his sleep at his home in Seattle, his wife, Clauda Cuellar Young, told ABC News. After joining the Army two days after the September 11, 2001 terror attacks, Young, who was confined to a wheelchair following his injury, became one of the first Iraq veterans to vocally oppose the war.

He starred in the 2007 documentary about his life called "Body of War," which was co-produced by legendary TV talk show host Phil Donohue. A year later, Pearl Jam singer Eddie Vedder released the song "No More," a powerful call to end the war in Iraq that gave viewers a window into Young's life.

Cuellar Young said the couple had moved to Seattle a month ago after she claimed doctors at the Veterans Affairs Hospital in Portland, Oregon, tapered down Young's pain medications, labeling him a "junkie." She hoped he could get his normal dose of medication if they relocated to Seattle.

"I don’t know why he had to beg, he fought for his country," Cuellar Young told ABC News. After seeing doctors in Seattle, they were told they would need to come back on November 24 to meet with the pain team. Cuellar Young said she had tried to stretch out her husband's pain medication to help assuage the "breakout pain" he'd suffer in the middle of the night.

"People say, 'He died peacefully.' I’m not sure how peaceful he was," she said of Young's death in his sleep. "He just left, he never came back. I don’t think it was peaceful. All we wanted was to be home and pain-free."

It appeared that Young had given up the fight in 2013, when after a decade of struggling with his paralyzed body, deteriorating health, intense abdominal pain that led to the removal of his colon and a pulmonary brain embolism in 2008 that made him less mobile, he said he would give up food, water and medicine until he died. But before starting his hunger strike, Young wrote a scathing letter to President George W. Bush and Vice President Dick Cheney, excoriating them for launching the second Iraq war.

"I write this letter, my last letter, to you, Mr. Bush and Mr. Cheney. I write not because I think you grasp the terrible human and moral consequences of your lies, manipulation and thirst for wealth and power," he wrote.

"I write this letter because, before my own death, I want to make it clear that I, and hundreds of thousands of my fellow veterans, along with millions of my fellow citizens, along with hundreds of millions more in Iraq and the Middle East, know fully who you are and what you have done. You may evade justice but in our eyes you are each guilty of egregious war crimes, of plunder and, finally, of murder, including the murder of thousands of young Americans—my fellow veterans—whose future you stole."

He had a change of heart, though, and decided to keep fighting. It was a fight Young was used to, one that he'd engaged in with an administration he said sent young men and women to die in what he called an unjust war and one he fought against a Department of Veterans Affairs demanding better care for himself and his fellow vets.

Young's mother, Cathy Smith, told the Los Angeles Times that she was glad her son wasn't in pain anymore.

"If Tomas Young could get up every day and be in the pain he was in and still speak out about the war, it made it easier for the other guys," she said. "He always said if we saved one 18-year-old from joining the military, that's enough. And he did."