The family of Curtis Cheng say he was a "gentle soul" and his murder has caused them "immense pain".
Selina Cheng was joined by her son and daughter to deliver her victim impact statement at the sentencing hearing of Raban Alou.
Alou pleaded guilty to charges of aiding, abetting, counselling or procuring a terrorist act when 15-year-old Fahad Mohammed murdered Mr Cheng as he exited NSW Police headquarters in Parramatta in October 2015.
Mrs Cheng told the court of the day four police officers appeared at her door and confirmed her worst fears that her husband was not coming home.
In her victim impact statement she recounted falling to her knees and weeping when officers gave her the news.
She described being "enveloped" in "total darkness", telling the court she was "deeply hurt and utterly repulsed" by anyone who played "any part in Curtis' senseless murder".
"We tried for years to make a good life for ourselves in this amazing country," she said.
Justice Peter Johnson acknowledged what he described as the "devastating effects" of the family's loss.
He told the family they had demonstrated dignity during court proceedings and passed on the condolences of the court and the nation.
During the statement, Alou kept his eyes trained on the ground.
He was wearing a green shirt with his hair in a low pony tail and did not rise as the Justice entered the room at the beginning of court proceedings.
The sentencing hearing continues.
