"He forbade my mother from seeing anyone in her family, just because they could see what he was like and what he was doing to her," Ben says.
"There were times when it was late at night and I'd be woken up because of screaming, I could hear him beating my mum in the lounge. I just felt cowardice, there was nothing I could do about it."
Ben looked for affection outside the family.
"I had the urge to always be in a relationship to make it seem like at least one person cared about me," he says.
Towards the end of the second term of his Year 10 year, he started cutting himself.
"I had seen it in blogs. I thought, these people do it and they've got some sort of release out of it," he says.
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"It was in a period between relationships. I wasn't getting any affection there, I wasn't getting any affection at home, and I felt like I had no feelings, so with self-harm I felt pain."
He was living in the only downstairs bedroom, emerging only to eat and shower.
The first time, he got a blade by breaking open a pencil sharpener. Later he used a razor blade. He cut his thighs and his shoulders, always places that could not be seen.
He cut every couple of days through most of the rest of that year.
"Looking back on it, I'm not sure why it was. I couldn't feel any other feelings. I thought I was inhuman for not feeling, so if pain was the only thing I could feel, that would at least reassure me that I was still human," he says.
As far as he knew, his mother never noticed. "That was what made it worse - my mother, the person who gave birth to me, couldn't even tell that I was going through something that tough," he says.
He stopped cutting when he found a new girlfriend towards the end of that year. Early in the next year, he confronted his mother.
"I was just sick of the way I was treated. I said like, 'Mum you have to either get rid of him or me.' And she said, 'He gets home in about two hours, you'd better be gone by then.'"
He slept at a mate's house for two weeks, then used Facebook to track down his maternal grandmother whom he hadn't seen for seven years. "She was like, 'We have a spare room, you're more than welcome to come here.'"
He didn't see his mother again until he ran into her in a supermarket three years later.
"She came over and said hi as if nothing had happened, and I just got so mad at that. I said like, 'It's been three years, there's got to be more to try and sort this out!' And she just called me a prick and walked off. I haven't seen her since."
So Ben has made his own life. His grandparents helped him to develop goals for the first time. He left school at the end of Year 12, did a six-month retail course, then started an audio engineering course.
His school counsellor helped in those two years after he left home.
"We just talked a lot," Ben says. "I couldn't see any way to sort the situation out, and with him being a fresh set of eyes he would say, 'Why don't you try this?'"
In his Year 12 the school sent him on Gateway work experience one day a week to the Zeal youth centre in Henderson, where he learned sound engineering and made new friends. He still volunteers there.
He left the audio engineering course to work fulltime when his grandfather developed cancer. The cancer makes him feel powerless all over again, but the older man's peaceful acceptance and determination to "live in the moment" give Ben hope.
He has problems, of course, but they are the normal problems of relationship breakups, his grandfather's illness, moving flats and changes at work. Now he can feel the normal feelings.
"It's not as bad as it used to be," he says. "I have definitely come out the other side a lot better than most people do."
WHERE TO GET HELP
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youth services: (06) 3555 906
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (4pm to 6pm weekdays)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• The Word
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• CASPER Suicide Prevention
If it is an emergency and you feel like you or someone else is at risk, call 111.
