It's a shocking story for any son to tell about his father but for Kenyon, it meant the end of a traumatic and often frightening childhood. His dad Edward's behaviour meant the family was permanently on tenterhooks, waiting for the family's "secret" to be outed in public.
"For years, Mum and I would cover for him when we went out, making sure nothing happened. We'd always be 'on', keeping one eye on him and watching for the signs, then getting him home before anybody noticed."
And, invariably, they managed to cover his tracks.
"Dad was a nice guy — everyone liked him. He was a functioning alcoholic who held down a job. You'd never know he was an addict. People didn't see what went on once we were behind closed doors."
Kenyon is reluctant to go into detail about what happened at home, but the effect his father's alcohol abuse had on the family, especially his mum, Paula, is evident.
"Mum took the worst of it and it was often brutal. He would say really terrible things, call her everything under the sun. Dad was never honest about his drinking, either to himself or anyone else but I knew he was ashamed and embarrassed — alcoholics usually are. He just couldn't admit it.
"A couple of times, usually after a bad bout, he went to a couple of Alcoholics Anonymous meetings, but it never helped. I remember him going to one meeting and buying a bottle of vodka on his way home.
"Alcoholics need help. I tried asking him, ignoring him, arguing but nothing ever changed."
That is, until Kenyon turned 20. "Until then I'd kept everything quiet, been complicit in hiding Dad's addiction. But I got to a point that I realised I didn't want to pretend it wasn't happening any more."
The actor has accepted he had no say in the choices his father made that led to his death but he is also still angry at the suffering he and his mother went through — which is why Kenyon was the only person to speak at his father's funeral.
"I didn't want some Disney-esque version of Dad's life to be told by people who were looking at him through rose-tinted glasses," he says.
"Dad killed himself because he was drunk and, as a family, we all suffered because of his alcoholism. Alcohol addiction is an incredibly selfish illness. I find it hard to hear an alcoholic say proudly that they haven't had a drink for five months, or they are 16 years sober.
"Of course that's good, but they don't think about the families who have had to live with the pain and suffering that's caused and don't get any support. They are the victims."
Kenyon is acutely aware of the pitfalls of drinking — his grandparents were also alcoholics — but still enjoys a drink.
"It's like sex — you can have safe sex without choosing never to have sex at all, and you can have a drink without it being this terrible thing — an alcoholic can never have a single drink, ever again in their whole lives, but not everyone is an alcoholic, and I don't think everyone should stop drinking if they enjoy it.
"Alcoholism is so much more than just how much we drink. There is a big difference between getting drunk at the weekend and being an alcoholic.
"The reason I'm doing Dry July and talking about my own experiences is because I want to take the taboo out of talking about alcohol. Alcohol is such a huge part of our lives in New Zealand — it's part of our culture.
"When do we ever see mates, go to the beach, go to each others' houses and we aren't having a beer or a wine? It's part of our everyday lives."
And despite his history, that's okay, says Kenyon, as long as we're honest about our drinking habits. Kenyon is enjoying the novelty of going dry for July, but is also looking forward to a time he can enjoy a beer again — especially after work.
"I have gone a month without drinking before, when I was training for Step Dave, but I'm not doing this with anyone, so it won't be easy," he said. "Not going out for a beer with the cast and crew after we finish the play every night will be weird."
Warning signs
• Isolation or frequent absence from work or commitments, or difficulty keeping everything in order.
• Someone who needs a drink will suffer withdrawal symptoms, including anxiety, nausea and sweating.
• Alcoholics suffer from anger or depression, and may become emotionally unstable.
• Taking more risks, eg, driving drunk. As their judgment becomes more impaired, an alcoholic will increasingly put themselves, and others, in dangerous situations.
Where to get help
• Alcohol Drug Helpline: alcoholdrughelp.org.nz or 0800 787 797
• Alcoholics Anonymous New Zealand: aa.org.nz or 0800 229 6757
Dry July
• Fundraiser challenging New Zealanders to go alcohol-free for a month
• Money goes to helping those with cancer
• For information or to donate to Jono Kenyon visit www.dryjuly.co.nz