A woman who saw her mother kill her father broke down in tears as she described seeing him on the floor bleeding "bright red blood".
Jeyamalar Kumarathas, 55, admits manslaughter but denies murdering her husband Kumarathas Rajasingam, 57, at their home in Norfolk on 16 March.
A video of a police interview with Elaxana Kumarathas, 26, was shown to the jury at Norwich Crown Court.
She said she saw her mother stab her father near his rib cage.
Ms Kumarathas said she was sitting in the living room when the attack happened after a late family meal in Burdock Close, Wymondham.
She was not aware he had already been stabbed in the back.
Ms Kumarathas described how she managed to "loosen the grip" of her mother on the knife and put it in the sink in the kitchen.
In tears, she told the interviewer that when she returned she saw her father's body on the floor.
"I looked up and saw my mum standing over him, just shouting at him. I could not understand what was happening," said Ms Kumarathas.
Opening the case for the prosecution, Christopher Paxton QC told the court that just before midnight the couple and their two adult children Elaxana and Jesse finished a meal, during which a lot of alcohol had been drunk.
Mrs Kumarathas threw insults at her husband calling him a "sleaze and a womaniser".
Mr Paxton said she stabbed Mr Rajasingam in the back and stomach "without any justification or cause" as result of "unhappiness in her life, fuelled by the consumption of alcohol".
He said the blade "pierced the skin to a 11.5cm (4.5in) to 12.5cm (4.9in) depth".
The trial continues.