The recipient of a top bravery award hopes his win will lead to a discussion about mental health.
Luke Chilcott tried to defuse Greg Floyd moments before he killed his wife, Ora Holt, before turning the gun on himself.
Mr Floyd had chased his wife into Mr Chilcott's home while armed.
Mr Chilcott's actions allowed six children inside the home to escape.
Three fatal gunshots were fired as they fled.
Mr Chilcott was honoured with a gold medal during a ceremony in Wangaratta on Thursday.
He said he had only decided to accept the Royal Humane Society of Australia honour in the hope it would raise awareness of mental health issues.
"It takes a lot more strength to ask for help than it is weak," he said.
"With more support or just reaching out for help, this could have been all avoided.
No-one wants to be in a situation like that. I think the word 'hero' gets thrown around a bit but I think he actually is one.Detective Leading Senior Constable Wade Spokes
"The reason I accepted the award - because I had no intention of doing so - was to use it as some sort of vehicle or platform to get recognition for mental health and to get people to think twice."
The late woman's family members and police involved in the 2017 incident attended a small ceremony at Mr Chilcott's home.
He received his medal from Detective Leading Senior Constable Wade Spokes on behalf of Victorian Governor Linda Dessau.
The detective said the term hero was overused, but it definitely applied to the Wangaratta man.
"I couldn't think of a more deserving winner," he said.
"No-one knows what they will do when they're in a situation like that.
"No-one wants to be in a situation like that.
"I think the word 'hero' gets thrown around a bit but I think he actually is one."
He felt he was being set up for something, that his wife was having an affair, and that she was using drugs.
"The available evidence suggested that he may have suffered from a delusional disorder," the coroner said.
The impact of the murder-suicide has led to Mr Chilcott seeking assistance and support.
"I spent years doing therapy sessions as just about everyone from this situation has," he said.
"That's helped me.
"I didn't do the blokey thing of 'she'll be right'.
"I did a little bit to start with but without the psychological services and reaching out for help myself I could have been added to the list.
"It's just easier, even though it doesn't feel like it at the time, to say you're struggling.
"All of that caused this in some way, shape or form."
The more he has opened up about the traumatic ordeal, the easier it has gotten.
"A problem shared is a problem halved and I think that's very true in this," Mr Chilcott said.
"It's horrible to talk about, horrible to go back over it, but at the same time it's part of the process.
"I don't love talking about it but it has to be talked about.
"It's important people know that mental health is a huge problem and it can have massive, massive ongoing effects on people."
He thinks less often about the incident with the passage of time, but certain things can trigger memories without warning.
"It's certainly something that hasn't stopped replaying, and I don't think it ever will," Mr Chilcott said.
"I don't think you'd expect it to ever disappear but it's a little bit easier than it used to be."
The two families had lived next door to each other for years before the incident.
Their children had played together and Mr Chilcott said they were just like any normal families.
The coroner's findings were as much of an eye-opener to him as anyone, he said.
He didn't spot any red flags.
"This was as much of a shock to us as it was to anyone," he said.
As the incident unfolded Mr Chilcott tried to prevent the armed father from entering his home as Ms Holt and her children hid.
He spoke to him after he smashed a window to get inside as Mr Floyd pointed a gun at him.
Mr Chilcott said he didn't think during the incident - switching to instinct - as he feared for his own family's safety.
"Just get his attention ... this is bad ... how do we make it less bad," he recalled.
"What do you say if you're in that situation?
"How do you process the situation, let alone what do you say that might have an effect?
"I asked 'what are you doing, you don't need to do this'.
"It was a one way street, a one way conversation."
Because of the horrific outcome, with four children left orphans, Mr Chilcott was reluctant to be recognised with the bravery award.
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"There's always the what-ifs and the could-ofs, but I try not to walk down that street anymore," he said.
"It took a long time to do that.
"It is what it is now."
Moving forward, the Wangaratta man says he will continue to do what he can to support mental health services which he said were sorely lacking for those who need them.
"Any mental health initiative I'm able to be a part of, I'm always the first to jump on board.
"|'ll continue to rattle cans and make phone calls and do whatever it takes to make people know it's not weak to speak out.
"It's really not."
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