Warning: Distressing content.

The early days had been filled with torrents of warm and passionate exchanges.

“Happy one month … today’s just going to be amazing thinking about you all day like I do every day … I’m in love with you, I fell for you instantly,” Anthony Monteleone said in voice messages to his partner in March 2024.

“Oh my god, you’re just you’re just a good guy … I just want to cry … with happiness and joy,” she replied.

But things took a “darker turn” weeks later when the woman broke up with him, having seen messages on his phone sent to other women despite their agreement to date exclusively.

Within weeks the woman was lying on the floor of her gym’s underground carpark in Sydney’s inner-west, Monteleone having sneaked up on her and stabbed her repeatedly in the neck and chest in a “ferocious and terrifying” attack.

Details of his obsessive behaviour in the weeks before the attack and previous domestic violence offending can now be revealed in documents tendered to the court and seen by NewsWire.

Monteleone had begged the woman in a series of text messages and voicemails to “let us give this a chance please” after the break up, but she urged him to respect her wishes and leave her alone, telling him he was being “forceful” and “obsessive”.

“Do you realise how sick this is? That I actually have to get my mum and dad to sleep here because of you, because of the way you’re making me feel?” she messaged him.

“I am in tears right now I can’t believe it got to this I would never ever try anything to hurt or scare you,” he replied.

Monteleone kept pleading, telling her he just wanted to “speak to you every now and then”, “I love you with every single inch of my body”, “I miss you so much”, and “I think about you every single second of the day”.

The woman even told him he would find someone else who would love him, but he replied: “I don’t want anybody else ever.”

She called the police on him after a couple of days on April 19, prompting him to leave a voicemail saying: “the police just called me and I am not upset with you honestly I just want to say I deeply apologise for all this from the bottom of my heart”.

Anthony Monteleone's "obsessive” behaviour towards his ex-girlfriend in the weeks before he stabbed her in the neck have been revealed in voicemails released by a court.

Monteleone then called her 115 times the following day between 5am and 3pm on a series of social media platforms. Hours later police served an apprehended violence order on him.

“He continued to hold out the hope … that he may be able to patch things up,” Judge Abadee told the NSW District Court on Friday.

“In this, he was utterly delusional.”

Monteleone was convicted of breaching the AVO on April 29 – including by following her home – with a magistrate warning him that his behaviour would land him in jail if he continued.

The very next day he saved a screenshot of the woman’s home from a real estate website, and searched her name and business online in the days following.

His mind then “took on a darker turn” by May 8, Judge Abadee said, with Monteleone grabbing a knife from his kitchen, getting in a car he knew the woman had not seen before, driving to a cafe near the woman’s home, and then making his way to her gym.

He waited in the car park for 40 minutes before sneaking up on her and stabbing her in the neck and chest in what was described as a “ferocious and terrifying” attack in court.

He continued to stab her for 25 seconds before two bystanders stepped in, with Judge Abadee finding Monteleone likely would have killed the woman if not for the brave intervention.

Domestic Violence helplines

Images released by the District Court of NSW show the blade of the knife Monteleone used snapped off at some point during the attack.

The court was also told the woman was not the first to take action against Monteleone, as he was convicted for stalking and intimidating another woman years before the stabbing.

‘Warning signs’ should have been enough: Woman speaks of attack

The woman chose to read out a victim impact statement in court, Monteleone watching on an audiovisual link from prison as she said the “warning signs” should have been enough.

“Action must come before violence, not after,” the woman said.

“What took seconds became a fight for my life.

“Not every woman survives. Today is not just about what was done to me, it’s about recognising the seriousness of this kind of behaviour and ensuring it is not minimised.

“I stand here not only for myself but for … those who never got the chance to stand here at all.”

‘Just lashed out at her’: Monteleone’s police interview

Monteleone fled after the attack, driving around before torching his car at a park and walking home.

He turned himself in to police the following morning after visiting his family and apologising to them.

Monteleone told police he “just lashed out at her” and that it “was all too fast” in a chilling interview released by the court.

“Did she seem hurt?” an officer asked him.

“At the time? Mm, no,” he replied, telling the officer she was “just probably screaming, yeah” when asked if the woman was making any noise during the attack.

Asked about whether he was jealous at the time about the woman potentially seeing other people, he told police: “Just, you know, what couples go through or how they express after a relationship is over, you know?”

Monteleone was found guilty of one count of cause wounding/grievous bodily harm with intent to murder (domestic violence) earlier this year following a jury trial.

Judge Abadee accepted Monteleone suffered from an adjustment disorder at the time of the stabbing but found it did not significantly reduce his moral culpability.

Monteleone was on Friday sentenced to 13 years imprisonment with a non-parole period of eight years and seven months.

He will be eligible for release in December 2033 at the expiry of his non-parole period.