She told her that Jennison had a history of violence against women.
Prosecutor Brian Berlyne told Jennison's sentencing hearing that he had 13 previous convictions.
Following the case, Ms Hill has released images which graphically illustrate her ordeal to raise awareness of the realities of domestic violence.
Ms Hill said she was attacked after Jennison had returned home from work.
It was my son - I had been unconscious half-an-hour.'When Ms Hill was discovered by her son Wade, her arms had been tied up with black electrical flex cord from the microwave, and she had been placed inside a sleeping bag.
Before Jennison left, he had called Wade and told him to come to the house, claiming his mother had taken some tablets and had grabbed a knife, and that he had tied her up for her own safety.
The court heard that when Wade arrived, he thought his mother was dead.
Jennison, who had prior convictions for violence against women, was jailed for three years and three months by Manchester Crown Court.
He also faces a further three years on extended licence upon his release from jail.