The wife of a man accused of murdering his former lover in her Sydney home has denied it is in her best interests that he is convicted.
Theresa Mulvihill told the Supreme Court on Thursday that her husband had called her saying "she's gone" on the day Rachelle Yeo was stabbed to death at her home in Sydney's north on July 16, 2012.
The next day she said the 46-year-old called her from Sydney Airport, saying he was trying to get on a flight but that there "were a lot of police around".
Paul Mulvihill has pleaded not guilty to Ms Yeo's murder, saying he acted in self defence after his former lover attacked him.
The court has heard the pair had struck up a romantic relationship while they were both working for Sanofi-Aventis pharmaceuticals.
Just days before Ms Yeo's death, Ms Mulvihill, who had known about their affair since January, said she finally called it quits with her husband.
After the conversation, she told the court Mulvihill had come into a bedroom where she was in bed, had put a pillow over her head "and pushed it down".
"It wasn't heavy but he had it over me and held it there," she added later.
After she pushed him away, he allegedly said to his wife: "It's not you it's her".
Ms Mulvihill said her husband never called Ms Yeo by name, always referring to the 31-year-old as "her".
She said her husband was crying "almost daily" from June up until Ms Yeo's death and had complained of being depressed.
Before Mulvihill left for Sydney on July 16, Ms Mulvihill said she had gone through his bag and found a white plastic chain.
She told the court that she had initially hidden the discovery from police in 2013, saying "I was trying to protect Paul at that time because we were getting along quite well".
Mulvihill's barrister Catherine Traill questioned her motives in giving evidence for the crown at her husband's trial, pointing out that if the 46-year-old is convicted she will be entitled to all his assets, including approximately $2 million worth of property.
"It's in your best interests that he is convicted," Ms Traill stated.
"I don't agree. He is the father of my children, I don't want him in jail for the rest of his life," an emotional Mrs Mulvihill replied.
"I'm here to do the right thing. I'm not trying to convict anyone."