The first woman to be convicted of having sex with a minor has spoken out for the first time, revealing details of how she ended up drunk in bed with the underage boy.

Briar Dravitski, 23, was sentenced in New Plymouth District Court last week to 240 hours' community service for two charges of having sex with a 13-year-old boy.

She is back in court tomorrow morning on charges of assault with a weapon - a telephone - and wilful damage involving her estranged husband's partner. Dravitski told the Herald on Sunday she believed the boy when he told her he was was 17 before they had sex for the first time.

When asked if the boy looked young for a 17-year-old, Dravitski said: "I mean, you can't tell these days can you? And the people who he was with were 17."

Dravitski, who has a history of mental health problems, said she and several others were at a friend's place in New Plymouth when she first met the boy and that initially she was not attracted to him.

"He came to my place with his friends," she said. "He'd been sleeping in a car. I asked why.

"The people who were there clarified [sic] that. He said he'd been kicked out of home."

Dravitski said one of her friend's parents gave their son money and another parent drove them to a supermarket to buy alcohol before they ended up back at her place.

"We all got drunk. There was only a couch, a spare bed and my bed. Of course, I've got a king-size bed.

"He [the victim] asked if he could crash in my bed because the others were taking up the couch and the spare bed. And yeah ... " Dravitski trails off, the regret palpable.

The second time she had sex with him she was caught. The boy's mother had found out where he was staying and walked in while they were having sex.

"She said, 'do you know old my son is?' I said, 'Yeah, he's 17'. She said, 'Actually he's not'."

Dravitski said she had a minor altercation with the mother before going for a walk with her to find the boy, who had run off.

Police were already on their way as the mother had alerted them previously to where her runaway son was staying.

By then, Dravitski claims, the boy's mother had taken pity on her.

"She was comforting me because I was crying. She had her arm around me and said it was all right," Dravitski said.

She said she went into shock when the mother told her the boy's real age.

Dravitski was arrested on September 25. "I was released from the cells at 3am [the next] morning. I got home and my house had been trashed. I just about lost it and tried to kill myself. I was admitted to the ward and that's where I spent the next five weeks."

The ward she is talking about is Taranaki Healthcare's Te Puni Waiora, a mental health unit. She is no stranger to the place, having endured four stints there since September last year.

Since she was 15 she has struggled with mental illness and has been on antidepressants since. Now she is on a cocktail of antidepressants, antipsychotics and valium.

"My parents split up when I was young. I didn't get on with my mother. I was in social welfare.

"I left school when I was 15, went flatting on my own at 15. I just started having trouble with depression and behaviour."

Dravitski's lawyer Pamela Jensen said Dravitski did not want to use her background as an excuse. She acknowledged she had done wrong and was now paying for it.

But worse than the 240 hours' community service and nine months' supervision is the public scorn.

The unemployed 23-year-old has been subject to a barrage of abuse since the arrest.

She has received abusive phone calls and text messages and has been verbally attacked by strangers and acquaintances alike.

"I've had nightmares for the past two weeks. I haven't been able to sleep. I don't go anywhere, I'm just stuck at home."

She knows why, knows a lot of people think that she basically "got off" and thought the sentence should have been much harsher.

Ms Jensen said the scrutiny her client had faced from the media over the past week had been unwarranted.

The lawyer is upset that a newspaper reporter was waiting outside her house the minute she was released from Te Puni Waiora.

Dravitski claimed she was "pilled up" when she gave the interview and agreed to be put up at one of the city's hotels in return for exclusivity.

Dravitski has lost whatever anonymity she had in a town small enough for the term "six degrees of separation" to be reduced to two.

Still, she's not thinking of leaving - she has a new fiance, a son who is about to turn 3 and she's never lived anywhere else.