After 20 years of misery, Lucille Scollay finally snapped.
She loved her husband Guy dearly. But after a night out drinking with an old flame, she felt their sad lives could not continue.
So, she got a large knife from the kitchen, straddled her husband as he lay sleeping, and plunged the blade deep into his chest.
Mrs Scollay denied murder.
And after a short trial at the High Court in Christchurch last month, a jury agreed.
Today, she was jailed for six years, with no minimum non-parole period, for manslaughter.
She has the support of both her family, the couple's son Louis Augustus, and her dead husband's relatives.
"Of all the cases I've ever worked on, this has been one of the most troubling in just about every sense," her defence counsel Rupert Glover said outside court today.
Mrs Scollay, 46, admitted stabbing Guy, 48, through his heart during the early hours of February 10 last year with fatal consequences.
She had become highly frustrated and dissatisfied with their lives, the court heard.
Her husband, a bright history major, became profoundly depressed shortly after the birth of their only child, son Louis, 20 years ago.
Mr Scollay was on anti-depressant medication and the methadone programme, barely left their house suffering undiagnosed agoraphobia, and was essentially bedridden with scabies. His only release was the smoking of cannabis.
His wife's family encouraged 'Lulu' to leave her beloved 'Guido' and "get her life back on track".
That night, she returned home after a night out drinking with a man she had become close to, Greg Van Dyk.
Walking up the long Edgeware Rd drive, she decided to kill her husband, the Crown contested.
"She took her husband by his shoulder as he lay sleeping on his side, rolled him onto his back, got on top of him, straddling him as he was still half asleep, brought the knife up and stabbed him in chest, a deep wound that penetrated his heart," Crown prosecutor Mark Zarifeh said.
Justice Cameron Mander today said it was apparent her actions were "borne out of despair".
She was conflicted, in that she was deeply unhappy, but she still loved her husband, and felt she could not leave him.
"This predicament led to this crisis which led to your killing of Mr Scollay," the judge said.
The violent act came at a "time of personal crisis," Justice Mander said.
She was accurate when she later told police it was a "moment of madness".
The judge told her she had to live with what she had done, and the impact it had had on her family.
Her defence claimed she only wanted to somehow shake her deeply depressed husband out of his funk and make him realise just how "desperate" their lives had become.
Defence counsel Rupert Glover said it was "almost superfluous" to say how much of a tragedy this was.
During his long career, this case was "quite unique in the way the whole thing unfolded".
It was not a wilful, deliberate or premeditated act, he contested, and her immediate horror afterwards bore that out.
No punishment the court imposed could make up for what her, and her family, had lost, he said.
The High Court was a court of justice, Mr Glover said, but said it was also traditionally a court of mercy.
"If ever there was an occasion in which that mercy should be exercised, then in my submission, sir, it should be today."
Victim impact statements from her son Louis and Mr Scollay's father Chris said they bore no grudge.
Louis spoke of empathy for his mother after all the years, Mr Glover said: "Not just sympathy but empathy."
He declined to comment as he left court today.
Outside court, Mr Glover said the defence will now contemplate their position over the length of the sentence.