To the world he was "an all-round good guy". He was a retail manager and a talented rugby player. He was respected. But at home, he was a tyrant who inflicted pain and suffering on the people he was supposed to love.
Mr Eparaima is not asking for sympathy or forgiveness. He is not justifying anything he did or making excuses. The reason he speaks out about his past is to teach other men what family violence is - and that it's unacceptable.
He works with the It's Not OK programme and speaks to groups, including the police, about his life, in a bid to educate them from a perpetrator's perspective.
By sharing his story, something he is deeply ashamed of, he hopes to help others.
"I started off mainly verbally and psychologically abusing," he told the Chronicle. "I minimised it by saying it was 'just' verbal abuse. I didn't see myself as being as bad as the guy that hit.
"My kids are adults now and it's what I used to say to them that they remember. The bruises disappear but the psychological stuff, that's what is left behind, that's what has done the damage."
Mr Eparaima said that in most cases, verbal abuse was the precursor to violence.
"After a little while the words start to lose their effect, though. The victims see them as threats; they are not having the same effect as they did.
"So, you have to step up your game to remain in charge. I would get right up in my partners' faces, I'd be spitting angry.
"I didn't have a gradual anger, we'd go from talking nicely and quietly to an outburst, just an absolute attack.
"The first time I was violent, it was a push. Even then I knew in my head that I had overstepped the mark - but at least it wasn't a punch ... I said 'sorry' and 'it will never happen again'. But from then I went on to be a perpetrator for more than 20 years."
Mr Eparaima "progressed" from threats and pushing. The neighbours would call the police but he was never arrested, never charged. He knew how to talk his way out of a situation, and his family never challenged him in front of anyone.
They knew what would happen if they told anyone about what dad was doing.
"From pushing, the next thing was a slap. Again I justified it - it was 'just' a slap, not a punch, so it's not that bad. After that I pretty much progressed to everything imaginable and unimaginable.
"There was punching, kicking, choking, spitting. I put butcher knives to the throats of a couple of my partners. The intention in my head was to take them out. It was pretty horrific."
Mr Eparaima was raised in an extremely violent home. By the age of 10, he was assaulting his mother. He was sent to boarding school, where again he was exposed to violence. As a new student, he was beaten and bullied. Then an older boy started to sexually abuse him.
It was just another episode in his violent life.
At 19, after he left school, he was charged with forcing a younger girl to do an indecent act. He was convicted, and on top of the anger that was building within as a result of being a human punching bag most of his life, he now had the shame of being convicted of a sex offence.
He is open when he speaks about all of this. All of this, combined, is why he was so angry, which in turn led to violence. Again, this is not his excuse - it's merely an insight.
"With a lot of perpetrators, society sees them as this angry, aggressive man, but most of us were victims once; we had to deal with some pretty adverse things in our childhoods.
"If that's all you know, that's all you know. Until you learn a new way or decide this is enough, you will always carry on hurting the ones you are supposed to protect and love."
Mr Eparaima can't remember all of the beatings he dished out, but the continual apologies are painfully clear.
"The word 'sorry' becomes a hollow word in a house like mine was. What you're sorry for today is going to be there again tomorrow or the next day. You feel stink, you are critical of yourself. You build up a good amount of self-hatred, which then just adds to the anger."
Control was also a big driver of Mr Eparaima's rage.
"For me, I was the king of the castle. That's how things went," he explained.
"I could be good for a few months but when the shit hit the fan I went back to what I knew worked: violence and put-downs ... I was an out-and-out arsehole."
Mr Eparaima's life only changed when a mate started to go to anger management.
He thought it was a good thing, that his mate "needed it".
"He was constantly violent. They didn't just send a police squad car to his place, they sent the armed offenders squad," he said.
"He said, 'I'm doing anger management,' and I said, 'Good on you, mate, because you really need it.'
"I never put myself in that category with him."
After weeks of his mate pestering him to come along, Mr Eparaima joined him.
"Initially, I thought it was a load of crap. They would talk about violence-free homes and I'd think, 'They're filling your head with shit, man, that's not the real world.'
"In all honesty, I didn't believe at the time that there was such a thing as a conflict-free world out there."
His mate persevered and Mr Eparaima stayed and completed the 23-week course. He immediately signed up to do it all again.
He also credits the woman running the course for forcing him to see himself as his partner and kids saw him - as a terrifying and abusive man.
Now 51, Mr Eparaima travels the country telling his story and calling for men to take stock, take responsibility and make changes.
He has been working with It's Not OK since 2011.
"And for the last two years, I've been contracted to the police as part of recruit training and going around talking to frontline officers. The aim is to give them a holistic view from a perpetrator."
He has apologised to his former partners - and his kids. He will be making amends with them until the day he dies and feels thankful that he has relationships with them and is able to be a grandfather to their children.
"My behaviour was bad, but not me. I'm not a bad person. It was my behaviour that needed changing - and it did.
"I can't take back my life or what I've done. And I am certainly not looking for forgiveness or to justify my behaviour. But if you can make a positive change in someone else's life then for me, that's the only way I can pay back.
"Stopping family violence is everyone's job.
"Lifting awareness is the only way we're going to stop this epidemic. There needs to be a change."