An Irish woman who killed her fiance in Sydney has told a judge of his repeated violence, including punching strangers and biting her all over her body, and his accusations of her sleeping with other men.
Cathrina "Tina" Cahill said she could not look at other men when she was out with David Walsh, nor could she look in the mirror when driving as there might be a male driver behind.
Cathrina Cahill being escorted into court last month. Credit: AAP
If she did, she said Mr Walsh would say: "I hope you got a good look slut".
The 27-year-old was giving evidence in the NSW Supreme Court on Friday at her sentence hearing for the manslaughter of Mr Walsh, 29, who was stabbed once in the neck in the early hours of February 18 in 2017 at the Padstow home they shared with two other Irish nationals.
Cahill was originally charged with murder but the Crown accepted her plea to the less serious charge on the basis of substantial impairment due to an abnormality of the mind at the time.
She testified that Mr Walsh blocked people from her Facebook account, deleted texts and numbers from her phone and was convinced she was having an affair with her boss.
Cathrina Ann Cahill and her fiance David Walsh in October 2016. Credit: Facebook
He would come to her work to wait for her and make a gesture - which she demonstrated - of running a finger across his throat.
Cahill told the judge of a string of incidents when Mr Walsh punched men - including his friend, Paul Mulligan, who had just arrived to stay at their house.
"I was in my bedroom and David came and out of nowhere started accusing me of being with Paul Mulligan which was totally untrue," she said.
"David came out and just hit Paul", who then moved out.
Another time she was with a female friend at a hotel when a man started talking to the other woman.
"David came in and hit the guy so hard he landed on the floor," she said.
"He said 'he won't look at my missus again'."
Mr Walsh punched numerous holes in the house walls, threw a glass bottle through a new TV and "would constantly break things in the house".
He would grab her face "and constantly bite me, that was his thing", she said.
A former housemate has testified that she saw Cahill stab Mr Walsh in the back of his head on October 3, 2015.
But Cahill testified that they had argued in their bedroom and she went to the door, but he blocked it and had a knife in his hand.
She went to grab it, he ran out and she cut the back of his head with the knife with a stroke.
The hearing is continuing.
AAP