Anthony "Tony" Eriksen, 64, stabbed his 59-year-old Lisa Fenwick in the heart and lungs, leaving her lying on the floor with a blood-soaked washcloth covering her wounds.
He was convicted by a jury in June over the murder which took place in the couple's Mascot apartment in Sydney's inner south in April 2023.
"The violence in this case led to the taking of the life of an innocent woman in her own home who was vulnerable and unable to break free from the shackles of their relationship," said NSW Supreme Court Justice Andrew Coleman while sentencing the murderer on Thursday.
Ms Fenwick had asked her partner to move out after supporting him for several years while he was unemployed.
She expressed her fears to friends.
"I am fearful of Tony. That is why I am telling you this," she texted.
"I just (need) to have a record if something happens to me."
In a triple-zero call, Eriksen told the operator he had got into an argument with Ms Fenwick and had "put a knife in her".Â
Declining to have lawyers represent him at trial, he hired a legal team before the sentence hearing only to terminate their retainer at the last minute.
As a result, Justice Coleman had no evidence about Eriksen's background or mental state which could have reduced his sentence.
"That is a matter of his choice," the judge said.
He repeated a quote by NSW Supreme Court Chief Justice Andrew Bell that domestic violence was a scourge on society before imposing a "de-facto life sentence".
The maximum sentence of 26 years and eight months means the 64-year-old Eriksen could spend the balance of his life behind bars, Justice Coleman said.
His sentence has been back-dated to his April 9, 2023 arrest.
A 20-year non-parole period will expire on April 8, 2043.
Justice Coleman noted that while Eriksen admitted stabbing Fenwick, he contended at trial that this was not voluntary.
The judge said the convicted murderer had shown no remorse or insight into his crimes.
It was only because of Eriksen's age when eventually released from prison that he would be unlikely to reoffend, the judge added.
The 64-year-old did not say anything before being escorted off by sheriffs.
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