On learning that the 53-year-old had cheated on her with a nurse in Manila on November 10, Niguidula punched him in the head outside the airport after spending hours crying in the bathroom.
A week later he was found stabbed and bleeding in the bathroom of their South Wentworthville home.
Attempts at resuscitation were unsuccessful.
At the time, Niguidula herself was having an affair with Apostol after she married his brother-in-law Jonathan Olivares.
When police were called after the 53-year-old’s death, Niguidula said his injuries were caused by his “stupidity” including by having an electric fan he was installing fall on his head.
She told police that her relationship with Apostol had been on the mend prior to his death and that she was having a happy time with him, going on the “perfect” date and having the best sex of her life.
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She pleaded guilty to manslaughter but denied she murdered her jilted lover.
A partial defence of substantial impairment, in which she claimed she had a mental health condition so severe she could not control her actions, was rejected by the jury.
Psychological evidence filed with the court showed a diagnosis of borderline personality disorder.
The matter will next come before Justice Hament Dhanji on June 9.
Crisis support is available from Lifeline on 13 11 14.
Support is available from the National Sexual Assault, Domestic Family Violence Counselling Service at 1800RESPECT (1800 737 732).