Tracey Kerr, 42, claimed her mother had had extramarital affairs, her father was an alcoholic and she had been abused by an older man when she was eight years old.

She had also had a heart attack at the age of 36, suffered from diabetes and been a heavy drinker from a young age, the court head.

Ms Kerr has pleaded not guilty in the Supreme Court to murdering Doug Barrett, 65, on May 25, 2012.

She admitted stabbing Mr Barrett, but later told police she did so in self-defence when he tried to rape her at around midnight in the bungalow behind his Echuca house.

Mr Barrett died from a heart attack after being stabbed in the neck and suffering cuts to his eyes.

Forensic psychologist Dr Aaron Cunningham told the jury he had diagnosed Ms Kerr as having post-traumatic stress syndrome and believed she was intellectually impaired.

Ms Kerr’s parents were raised in Moama and she had seven brothers and five sisters.

She felt no emotional connection to her family as her mother preferred the other children to her.

"Overall, she felt abandoned," Dr Cunningham said.

Ms Kerr told Dr Cunningham she was sexually assaulted by an older man in her home when she was eight and had to be hospitalised.

‘‘She didn't receive emotional support for having suffered that abuse and that aggravated these feelings of abandonment towards her family," he said.

Her education was poor and she struggled with school work. She could not read or write and her employment history was nearly non-existent. She has been on a disability support pension since 2005.

Dr Cunningham said Ms Kerr had her first child when she was 16.

"Primarily her relationships have been abusive. That ranges from emotional abuse, which I would categorise as being more neglect, to quite extreme physical abuse that's resulted in her being hospitalised, tortured, stood over, having her life threatened," he said.

"The first relationship she discussed with me was with a married man and then that led to abusive relationships with people where there was mutual drug abuse involved."

Ms Kerr claimed she was in one long-term relationship for 10 years, during which she had been attacked with baseball bats, screwdrivers and hammers, and was often locked up by her abusive partner.

Professor David Wells told the court he went to see Ms Kerr at the Echuca police station on May 26, 2012, after her arrest to determine if she was fit to be interviewed.

Reading from notes he had taken of their conversation, Dr Wells said Ms Kerr told him Mr Barrett had ‘‘tried to undress me’’.

"Touched me on the boobs, on top of clothes ... He kept saying I was beautiful ... I was the most beautiful black woman I have seen.

"[He said he] wished he met me years ago. Things he wanted to do to me. I said I really don’t need to hear this."

Dr Wells said Ms Kerr told him she had had six children to six different partners and they were now aged from 24 to 11 but had been taken from her by the authorities.

The trial before Justice Elizabeth Hollingworth continues.