That's the brutal alternative Jessica Silva believed she was facing when, with a knife in her hand, she finally stood up to her abusive ex-partner in a Sydney street following years of physical, verbal and emotional abuse at his hands.

It was Mother's Day in 2012 when her former partner, James Polkinghorne, arrived in an ice-fuelled rage at her parents' home in Marrickville, where she was staying after walking out on him several months earlier.

Mr Polkinghorne, 28, had sent text messages on his way over to the house in Livingstone Road, threatening to "cave" her head in and kill her.

When he arrived, Ms Silva, now 25, claims he punched her in the face before her brother, Miguel, stepped in to protect her, and Mr Polkinghorne began choking him.

Speaking for the first time publicly about the horror of that night, an emotional Ms Silva told the Nine Network's 60 Minutes how she stabbed Mr Polkinghorne in the street, killing him.

Had she not done so, she had no doubt she would not have survived.

"He really made me believe that he was coming to kill me," she said.

"I didn't want it to end like that."

She recalled how, terrified, she had gone into the house to get a knife to scare Mr Polkinghorne and get him off her brother.

"I wasn't thinking I was going to use it, I just grabbed the knife and then I went back outside with it, and I could just hear him screaming: 'I'm going to kill youse,' " Ms Silva said.

"I went slightly closer to him and then he looked up and he went to grab me again and to drag me back down to the ground, and he was punching my back at the same time, trying to drag me, and that's when I stabbed him.

"I don't remember stabbing him that many times."

Ms Silva was convicted of manslaughter last year, but was last month handed a two-year suspended jail sentence, with a judge describing the matter as "exceptional".

Ms Silva's lawyer, Adam Houda, told 60 Minutes that Ms Silva should not been charged with anything, and that he will seek a full acquittal in the Court of Criminal Appeal.

"If anything, she deserved an award for her bravery," Mr Houda said.

"We believe it should have been a complete acquittal. We believe it was a straight out self-defence case. And that's why we're appealing.

"We're very, very confident that the three judges sitting on the Court of Criminal Appeal will agree with us and exonerate her completely."

Ms Silva said she had fallen in love with Mr Polkinghorne after meeting him at the gym where she worked.

But soon she learnt he had a "dark side", recalling the first time he attacked her.

"He grabbed me by the neck and pulled me up against a wall, and he had me up just with his one hand up against a wall, choking me," she said.

"Then he let me go and then he just ran down the side of the road and just started head-butting the cars down the side of the road."

The abuse got worse, both physically and emotionally, she said. He repeatedly called her fat, ugly and worthless.

"Physically, I'd be thrown across the room, held over a balcony, pin me down, hold me down, just punch me, kick me," she said.

Three years on, Ms Silva says she still visits Mr Polkinghorne's grave weekly.

But she also had a message for other victims of domestic violence who were suffering, like she had, in silence.

"You need to let people know what's going on in your life. Don't keep it a secret," she said.

"Walk away, because it's only going to get worse, they're never going to change. Walk away at the very first sign. The 'sorrys', and the 'I won't do it again', it's all a lie."