A former soldier who killed his girlfriend and then himself at their Nova Scotia home had been on multiple tours in Afghanistan and came back psychologically "broken" and struggling with post-traumatic stress disorder, his family and friends said Friday.

The revelations came on the same day RCMP confirmed the deaths of 42-year-old Marc Poulin and 45-year-old Jennifer Lynne Semenec at a residence in Springhill were the result of a homicide followed by the man's suicide.

Both were from North Bay, Ont., and had recently moved to the Nova Scotia town. Their bodies were recovered from the small house on a dead end street on Tuesday following a suspicious fire at the home.

Shane MacDonald, a cousin and close friend of the former infantryman, said the family believes Poulin's PTSD was "the critical factor" in his behaviour.

MacDonald said Poulin was traumatized by deaths and violence he witnessed in three tours in Afghanistan and that the images haunted him in nightmares.

'We knew he came back broken'

In particular, he said Poulin told him about seeing a close friend die after stepping on an improvised explosive device, an incident he said also left Poulin with a traumatic brain injury.

He added that he and other family members had seen a written diagnosis in Poulin's personal records indicating he had PTSD.

"He internalized it. He told me he was getting treatment ... but he kept that close to his chest. You could tell he wasn't who he was before he went away."

An RCMP vehicle sits outside the house that caught fire in Springhill. (Craig Paisley/CBC)

Jason Hill, a childhood friend of Poulin's, said before the soldier served overseas he was constantly smiling and friendly, but by 2010 after his last tour of duty in Kandahar, Afghanistan, he was withdrawn and posted on social media about his trauma.

"He was openly sharing his struggles dealing with PTSD on Facebook and how the system wasn't open to him," recalled Hill, 42.

"We knew he came back broken."

Poulin plagued by 'illness and its demons'

A spokeswoman for the Canadian Forces said Poulin was a master corporal who served from January 1999 until he was released in February 2013, after being deployed first to Kabul and then twice to war zones in Kandahar. She did not reveal the reason for his release.

His last tour was to Kandahar from April to November 2010, a period when American forces launched a surge of military activity in the country.

Marc J. Poulin is shown in a handout photo provided by his friend Jason Hill. (Submitted by Jason Hill)

The Canadian military said Poulin served as an infantryman, a field engineer and a combat engineer, spending most of his career with the 2nd Combat Engineer Regiment in Petawawa, Ont.

The spokeswoman said the military could not comment on Poulin's medical treatment.

Poulin's wife, Shelley Foster — who Poulin left last year — told the North Bay Nugget that he "was different after he returned from duty," and was plagued by "illness and its demons."

Couldn't escape 'images and guilt'

She told the newspaper that the veteran's traumatic memories included trying to save a woman whose body was severed in an explosion.

"They ate away at him the most," she told the newspaper. "There was nothing he could do to escape those images and guilt."

The case has apparent similarities to another tragic homicide in Nova Scotia involving a veteran and his young family.

A public inquiry is being planned into the death of former soldier Lionel Desmond, who fatally shot himself, his mother, wife and 10-year-old daughter last year in Upper Big Tracadie, N.S.

His family members have repeatedly complained that Desmond, who served two tours in Afghanistan in 2007 and was later diagnosed with post-traumatic stress disorder, did not get the help he needed from the Defence Department or Veterans Affairs.

It was a perspective echoed by MacDonald on Friday.

Investigators surveyed the home in Springhill on Wednesday. (Preston Mulligan/CBC)

"There was a lot more that could have been done. The military should have an exit program for people dealing with this stuff," he said.

Jim Lowther, president of the Veterans Emergency Transition Services charity, cautioned in an interview that it may be premature to link Poulin's PTSD alone to the former soldier's suicide or Semenec's murder.

Other factors ranging from the brain trauma or other mental illnesses may play a role, he said.

He said in most cases of injuries from PTSD, it's the soldier or veteran who harms themselves, rather than hurting other people.

Call for a national treatment faciltiy

Lowther said Canada needs a national treatment facility just for veterans to assist them in making a successful transition from the military to civilian life.

"The military is letting people go before things are in place. The chief of defence staff said he wouldn't release anyone from the military that wasn't ready, but unfortunately it's still happening," he said.

A spokesman for Veterans Affairs Canada said the department has a well-established national network of around 4,000 mental health professionals who deliver services to veterans.

Marc Lescoutre said there is a network of 11 operational stress injury clinics across the country, as well as a 24-hour toll-free help line and short-term face-to-face mental health counselling and referral services.

Last fall, the military announced a suicide prevention strategy that seeks to reduce the risks of suicide across the entire military and veterans community.

Lescoutre said he couldn't comment on what treatment Poulin was receiving for his trauma.