Cricket is full of numbers, most of them fairly meaningless in the wider scheme of things. Tony Dell was the 255th man to represent Australia in Tests and took six wickets at 26.66 in his two appearances. But there are other statistics of far greater consequence for him.

"One veteran tops himself or herself in Australia every day of every year," Dell says. "In America it's every hour of every day of every year. In the last ten years we've lost more people to suicide than we've lost on the battlefield."

Unique in the world of cricket as the only Vietnam veteran to play Tests, Dell knows whereof he speaks. For 40 years he dealt in his own way with the memories, the horrors of war. He spent four decades back in civilian life before he was diagnosed with post-traumatic stress disorder (PTSD).

Looking back, it explained a few things. Like why Dell would always sit with his back to a wall whenever he entered a room. Like why he became a workaholic and gave up his cricket career early. Like why his marriage broke up and he became estranged from his children.

He describes his own case as "middle of the range", and knows that others have it tougher. Before he was diagnosed, Dell didn't even know that PTSD existed. He saw fellow veterans struggle with alcohol or drug abuse, down at the RSL (Returned and Services League, an ex-serviceman's club) getting smashed six nights a week. "You weak bastards," he thought. But now he knows. Now he's doing something about it.

Stand Tall For PTS is the official charity partner of the Prime Minister's XI match this year, to be played against England at Manuka Oval in Canberra on Wednesday. Dell started Stand Tall For PTS after being diagnosed and discovering the lack of awareness of the disorder, and the absence of help available for sufferers.

Gradually the organisation has gained traction. Prime minister Tony Abbott has given his support, hence the involvement in Wednesday's match. Angus Houston, the retired Chief of the Defence Force, is the patron of Stand Tall for PTS. Military personnel are susceptible, but so too are police, ambulance officers, firefighters - anyone exposed to traumatic events.

"There's no accurate figures, but there are estimates that up to 1.5 million Australians do have it to some degree," Dell says. "And it will never go away. If you could mend the memory then it might go away. But you learn to live with it. There are victims of crime, accidents, natural disasters, and it's the least understood and the least funded by the government."

Dell's own PTSD story began when he was called up for National Service in 1965. He ended up in 2RAR (2nd Battalion, Royal Australian Regiment) and in 1967-68 served in Vietnam before returning home at the completion of his National Service. He thought he would pick up where he left off, resuming his job in advertising and his cricket career with Eastern Suburbs in Brisbane.

"You're always taught that the strength of the section is only as strong as the weakest member... I always felt guilty about buggering off playing cricket when my workmates were still back there slogging away."

A tall left-arm fast bowler, Dell played for Queensland from 1970-75, and featured in two Tests, against England at the SCG in February 1971 and three years later against New Zealand in Melbourne. But he retired from the game at 27 and put all of his energy into his working life.

"It starts with a horrific trauma, in my case a couple of situations in Vietnam," Dell says. "You just get on with your life. You haven't got time to frig around in the Army. It's just, okay that happened, suck it up and move on. Or it can be just abject fear; there was one situation for me where I just shit myself for two or three hours.

"You move on and you put it into your subconscious and there it ferments. Eventually it re-emerges. I don't think that there were too many incidents until the early '70s. It can be bad dreams, flashbacks, night sweats, teeth grinding, fear of being in crowds. For 20 or 30 years if I went into a room or a restaurant or something, I'd sit with my back to a wall facing out.

"You can become a workaholic. I know in my case I'd get up at the crack of dawn, go to work and wouldn't come home until late at night because you're subconsciously keeping yourself busy and shutting out times when you can sit and think. A lot of guys can't handle it and start hitting the booze or drugs, substance abuse, and then it gets too much for a lot of people.

"My marriage busted up and my kids were estranged. You become very anti-social. My sister-in-law thought I was the worst bastard in the world. Now that she knows, we're on speaking terms again. That's what this is all about. There's so much misinformation out there."

Looking back now, Dell also realises that post-traumatic stress had a major effect on his cricket career. After the second of his Test appearances he told national selector Sam Loxton he didn't want to play anymore. Queensland captain Greg Chappell talked him into a fifth season of state cricket, but that was it.

"I'd always had this guilt trip," Dell says. "In the Army they teach you to kill, but they don't un-teach you. I just handed in my slouch hat and belt and they said, see you later, and next week I'm back at work.

"You're always taught that the strength of the section is only as strong as the weakest member. I carried that with me back to work, and I got in trouble at work sometimes when people were slacking off, and I lost a job because of that.

"I always felt guilty about buggering off playing cricket when my workmates were still back there slogging away, earning a buck, and I was still being paid. I just said to Sammy Loxton, I'm sorry but I don't want to play anymore. PTSD had a big effect on my cricket."

Like many people, Dell was shocked to learn he was affected by post-traumatic stress. It only came to light through a series of events that began in 2007 when he was invited to be the guest at a cricket challenge organised for defence force personnel from various countries. It was there that he first met Houston. It was also where a retired colonel asked Dell if he still had all his old medals.

He didn't. The colonel told Dell he should get them replaced. After months of phone calls reminding him that he could get these new medals, Dell gave in. He went to his local Vietnam Veterans Drop-In Centre in Maroochydore to set the process in motion. Then came a cup of coffee and a chat, and a startling observation.

"They said, 'You've got PTSD,'" Dell says. "I said 'bullshit'. They said, 'No, definitely.'"

Eventually Dell was officially diagnosed and given a pension; he was also told that there were thousands more Vietnam veterans like him who also suffered from post-traumatic stress. In 2009, he returned to the same international defence cricket event as the after-dinner speaker.

"I talked about cricket, Vietnam, PTSD moments," Dell says. "I finished off and got a standing ovation, which surprised me. It went on for what seemed like five minutes. Angus gave me a hug and the chief of the army congratulated me, because for the first time someone had come out and said they had PTSD and this is what it's done to my life."

There were sowed the seeds for what became Stand Tall For PTS. Those seeds are growing into something significant. Dell and Houston last year set in motion plans for a major national PTSD forum in Brisbane in September this year. Dell hopes the event will be a "who's who" of PTSD, complete with international guests. The aim is to end up with an action plan of genuine substance.

Of course, different treatments work for different people. Medication might help some PTSD sufferers but Dell has never been one for that approach himself. In a strange way, he finds his own best treatment comes from being the figurehead of Stand Tall For PTS.

"It's my therapy," Dell says. "I do this now 24/7 and it's just a continuation of the workaholic syndrome. One of the worst things that can happen when you get a pension is they tell you that you're only allowed to work eight hours a week. That's a trap in itself. What do you do? You just sit and think. You have to keep busy. So this is part of my therapy."

Brydon Coverdale is an assistant editor at ESPNcricinfo. @brydoncoverdale