April 17, 2002 is a date that continues to haunt Shaun Arnsten.

The Afghanistan war veteran was part of the 3rd Battalion Princess Patricia's Canadian Light Infantry Battle Group that lost four Canadian comrades and saw eight others injured in friendly fire at the hands of an American F-16 fighter jet near Kandahar.

"I was about 150 metres from the point of impact where the bomb was," Arnsten told CTV News.

In 2003, Arnsten, 38, was diagnosed with post-traumatic stress disorder, and a year later he received a medical discharge.

"I'm a young guy -- a soldier -- I went to war, I saw horrible things, I came back (and) I had a reaction to it," Arnsten said.

But the repercussions of his PTSD have affected his life back at home in Cochrane, Alta., as well.

Earlier this month, Arnsten says that he was rejected for mortgage disability insurance by Sun Life Financial because of his condition.

The veteran suffered a severe concussion in a motorcycle accident in April, which he says is preventing him from returning to his work as a heavy equipment operator.

Concerns about his financial situation prompted him to seek the coverage. Mortgage disability insurance provides a monthly sum towards mortgage payments, should a person become disabled.

So he filled out the forms, which included three years of his medical history, and sent them to Sun Life Financial.

And on July 12, Arnsten received a letter from the company that said that he was "ineligible … in view of (his) PTSD."

"I was really frustrated and angry to be honest," said Arnsten.

Sun Life Financial has declined requests for an interview, saying they value confidential relationships with their clients and it would be inappropriate to comment on an individual case.

Veterans Affairs Minister Erin O'Toole said his office is working to help Arnsten.

"We have a lot of control over what we can … in terms of benefits and programs," said O'Toole.

"Some of the third-party insurers … we've got to look at how we can address those if we can."

Despite the promise of help, Arnsten feels penalized for his PTSD.

"I did a job the government asked me to do (and) I did it to the best of my ability. I was injured during that but now I lack the ability to have the privilege of protecting my investment (and) my house," said Arnsten.

With a report from CTV's Alberta Bureau Chief Janet Dirks