Robin and Kerry took a smiling holiday selfie on a mountain. Minutes later, he killed her.

Robin and Kerry Michael had just hiked Tasmania’s Mount Roland and had a picnic lunch during their holiday around the southern state. The married South Australian couple were on their way down the mountain when they stopped to take a happy photo of themselves enjoying the trip.

Looking at the photo, taken at 1.01pm on February 11, 2015, no one would guess that just minutes later Robin would attack and kill his wife.

The 63-year-old’s brutal murder of his 44-year-old wife was the subject of a coronial inquiry of which results were released on Thursday and published by News.com.au.

The findings include explanations of what led to the woman's death, the details of the attack, and what her husband did next. The inquest was necessary because Robin Michael took his own life in Risdon Prison near Hobart in June 2015 after pleading not guilty to a murder charge.

It was found that Kerry was bashed to death with rocks by her husband after, investigators believe, the pair got into an argument.

In a Facebook post Robin posted in the hours after his wife's death, the man suggested that he accused his wife of having an affair and killed her over it.

"I have committed an act which should attract no pity, no sympathy, not even any understanding. I can’t understand it," he wrote.

"That it was an effect, rather than a cause, bears no consequence. It was not appropriate, necessary, nor anything really other than pure evil."

He said the man he thought his wife had an affair with was a close friend.

"The other party is [man's name], one of the people closest to me and the non-family member that I have sought to do the most for since I met him."

"So why would he think he has a right to engage in an affair with someone that he knows is the centre of my life."

In the post, Robin described his attack as a moment of "insanity".

"In the heat of the anger with Kerry’s admission, I had no control or influence over myself."

"To say I cracked and lost it when our quiet mountain descent got real would not do justice to the situation."

However, Kerry's family and friends believe that his accusations of an affair were totally baseless, and that is also what the coroner found, News.com.au reports.

"Tasmania Police actively investigated the suggestion of an affair in the aftermath of Mrs Michael’s death," Coroner Simon Cooper said. "Absolutely no evidence of the supposed affair was uncovered."

Cooper added that Robin had previously accused a former partner of having an affair with the same man - who has since sworn under oath that he hadn't had affairs with either woman.

Robin, the coroner found, had been "extremely jealous", "controlling" and "violent" to former partners.  Notes that Kerry's son Nathan uncovered, written by his mother, backed up this assessment.

"They outline issues with the relationship between her and Mr Michael dealing with his possessiveness, jealousy and the fact that Mrs Michael felt “trapped” in the relationship."

As for Robin, after leaving his wife's body on the side of the mountain and writing his confessional Facebook post - which alerted family to call police - he attempted suicide. He was found at a caravan park and taken to hospital, where he told police what had happened.

His death in custody in June 2015 is also the subject of an inquest.

If you or someone you know is impacted by sexual assault, domestic or family violence, call 1800RESPECT on 1800 737 732. If you are experiencing crisis or suicidal thoughts, please phone Lifeline on 13 11 14.