They were the glamour couple who had it all: fame, wealth, good looks and a baby on the way.

But chart-topping singer Joshua "J" Williams' former partner Larissa "Leo" Brown has broken her silence to reveal the domestic abuse behind the glamorous facade.

The couple split two months ago, shortly before the birth of their infant son.

J Williams, 24, was the Number 1-selling artist on the New Zealand singles charts last year. He is considered a role model for Pacific Island youth and Auckland mayor Len Brown named him in his "First XV" of public figures who will help showcase the city for the Rugby World Cup.

Now, Women's Refuge is calling for him to be dropped as a Cup frontman if he can't take responsibility for the abuse.

"He's got a chance to become a role model and show good behaviour, but what it takes is for him to stand up and accept it's wrong," said spokeswoman Kiri Hannifin. "He can't hide behind alcohol and anger as an excuse for his behaviour."

Williams' music and style has been compared to US R&B artist Chris Brown, on whom he says he models himself. But the American was convicted of a prolonged assault on his then girlfriend Rihanna in 2009.

And now, Williams has told this week's NZ Woman's Weekly that he too did things to his partner for which he was deeply sorry.

That hasn't impressed Larissa Brown who told the Herald on Sunday: "Actions speak louder than words."

She was limited in what she could say due to a contract she'd signed with the magazine to tell her story in next week's issue. However, she went on to say that her ordeal with Williams had been "horrible".

"The whole experience for me has been devastating. It's a shock to close family, friends and mutual friends."

The 26-year-old celebrity stylist gave birth to baby Ryder Leo after going into early labour. It was in those difficult and uncomfortable final days of pregnancy that Brown ended their two-year relationship.

"We broke up and then the baby arrived," she said. She is now living south of Auckland, managing to care for her baby and run her business with her mother's support.

Asked if she had a message to other women in abusive relationships, her reply was simple: "Speak up."

"Celebrities are no different to everybody else."

Now that she was telling her story publicly she felt "surreal".

"I feel a lightening," she said.

A close friend revealed how she'd seen Brown's bruises, and was relieved when the couple split, and pleased the story was now being told. "I don't want young people to look up to this guy any more," she said.

And a source told the Herald on Sunday of seeing Williams "man-handling" Brown outside a nightclub on the night of last year's Pacific Music Awards - after he was named best Pacific male artist. She was shocked that the many bystanders failed to intervene.

"I thought if this is what you do when people are around, I'd hate to see what you do when no one's there."

Police had also been called to the home Brown and Williams once shared in Mt Wellington, after altercations. She suffered fractured fingers after falling during one such row, she said.

In this week's Woman's Weekly, Williams appeared to downplay the level of violence.

He said he regretted his actions but added: "Just like every other relationship there are scuffles, here and there. I'm trying to right my wrongs."

He blamed alcohol for his abusive nature and anger problems, saying he began drinking at age 14 and grew up in an abusive environment.

Williams wrote his hit song You Got Me for Brown, and told the magazine that he left because he fell out of love.

He was now undergoing church-based counselling, he said. But after everything that had happened he still hoped he could be a good role model and father for his son.

Eddie Bennett, boss at Williams' record label Illegal Musik, said he couldn't comment on the revelations without having first read Williams' story.

Mayor Len Brown couldn't be reached for comment last night, but Rugby World Cup 2011 spokeswoman Joanne Perry said it would be premature to comment on whether the revelations would affect Williams' ambassadorship.

"It would be up to the mayor to review any membership. We would want to talk to the individual to make sure we get the correct information."

She said in choosing the First XV people were spoken to at length to decide who would make the best ambassadors, but background police checks weren't part of the process.