"If you walked in here right now as a combat vet and I can see your eyes are glassy, you just hit a child or put your hand through a window, I could have you in counseling by four o'clock," Davis said during a recent morning interview.

Davis, now 40 years detached from his own tour in Vietnam, still has problems with loud bangs, which cause him for a second to scan the area for a place to hide.

These days, Davis helps returning guardsmen and reservists register with the VA, and he talks to them about their benefits, which include coverage of treatment for PTSD. Seeking that treatment, however, is up to the vet, many of whom, like Roy, are reluctant.

"There's a perceived stigma," Davis said. "They're taught to be self-reliant — they have a 'warrior' ethic."

For almost 30 years Roy chose to handle on his own what he considers to be an elevated form of PTSD.

Roy said it's not fair to liken what Iraq and Afghanistan veterans are going through to the Vietnam he experienced. He went for weeks without a shower, bed or hot meal. Roy said the level of daily violence for U.S. troops on the front lines in Vietnam — and the stress that came with it — was much worse than what's happening in Iraq.

"You can't compare the two, as far as I'm concerned," he said.

Roy even used his first paycheck in Vietnam to buy a new rifle from the South Vietnamese — his second paycheck went toward a better backpack than the one he was issued. More betrayal, the way he sees it.

"The Army got everything," he said. "The Marine Corps, we got crap."

In Roy's case, he felt he had been betrayed too many times by the government to trust that it could help him. Now, however, he credits the counseling he receives through the VA with saving his life.

The rest of Roy's story

Roy was drafted out of college, a fact he credits for being a "pretty upset Marine" from the start.

"I didn't subscribe to the Vietnam war to begin with," he said. "I thought it was a place we shouldn't be."

Roy's feelings of betrayal by his own government started during training, which he said was rushed.

"We were just another number," he said. "Just another body to dispose of."

During basic training, Roy thought of becoming an officer and going to flight school. Instead, Roy said, other officers made life difficult for him when he wouldn't commit to serving more time in the military than he wanted.

"From that time on, it was downhill for me," he said.