Victorian police told Rosie Batty that if her former partner tried to kill her or their son Luke they would not be there in time to protect them, she has told an inquest.
Ms Batty took to the witness stand on Tuesday at the inquest for her son Luke, who was killed by his father Greg Anderson at a public cricket ground earlier this year.
An extremely distressed Ms Batty broke down several times as she tried to describe what it was like living under the constant threat of Luke's violent father.
Anderson killed the 11-year-old, Ms Batty's only child, after his cricket training at the Tyabb cricket ground in February, in front of dozens of other children and their parents.
The inquest heard on Monday Anderson had arrived unannounced and Ms Batty had considered calling triple-0, as she had done on other occasions, but did not want to embarrass Luke in front of his friends.
Today she tried in anguish to explain the circumstances leading up to Luke's death.
"We locked the doors... we had a baseball bat in one bedroom, we had a baseball bat in another bedroom," Ms Batty said.
"This is what I was living with. The police were telling me we can't be there in time if he wants to kill you... perhaps you should consider moving back to England.
"Every time it got worse."
Ms Batty became increasingly distressed, repeatedly thumping the witness box with her hands as she recalled Luke's father's behaviour and her powerlessness to stop him.
"I didn't know how to take the step and tell him, you can't see your son," she said.
"I couldn't do it. I so wanted him to take out his hatred on someone else."
At the same time, Ms Batty told the inquest she felt "really sorry for Greg... he loved him (Luke) so much."
"This mental illness was sabotaging everything in his life," she said.
"For me to stand between him and his son... Luke always had a really good relationship with Greg."
I didn't think this could happen: Rosie Batty
Ms Batty reiterated she always believed she was the target of Anderson's aggression and hatred, not her son.
"I still struggle to understand how it happened... I didn't even know what filicide (the act of killing one's own child) was," she said.
"I knew about Darcey Freeman, I knew about the Farquharson boys... but I didn't know what Greg was capable of... that he was capable of killing. He loved him (Luke).
"It couldn't happen in a public place at a bloody oval... I didn't think it could happen."
Ms Batty also said she was left waiting for police in fear on the roadside for almost an hour on at least one occasion, only to be told they did not have an arrest warrant ready to detain Anderson.
"Do you know how incredibly stressful it is to dob in a violent man in front of his son, and wait by the side of the road?" she said.
"They said the arrest warrant hadn't arrived... I went hysterical."
Ms Batty said she then had to go through the same experience the following week.
"I (was) always on my own fighting this man," she said.
DHS offered Rosie Batty counselling
Ms Batty told the court before her son's death she wanted other people to help her to make decisions because she "was stressed out of her brain".
She was critical of the Department of Human Services (DHS), who repeatedly offered her counselling.
Ms Batty said while it was helpful it was not the only solution.
She said that no-one spoke to Anderson about his behaviour and if he had stopped being violent she would not have needed the counselling.
She also told the court she felt like she had to keep it together all the time because no-one wanted to deal with an "irrational woman".
"I didn't want all the responsibility to be on me, I wanted other people to help me make decisions," she said.
During her evidence Ms Batty said everyone thought she was the one in danger and the risks to her were always discussed. She said she never thought Anderson would kill Luke.
Ms Batty said her son's death happened on a day when she thought he would be fine.
"If I had called the police can anyone tell me we would have been fine? This was a pre-meditated act," she told the court.
"It was to get at you... someone wants to make you suffer the rest of your life."
The inquest continues.