When suspicions of her boyfriend's infidelity were confirmed, Elisha Browne "saw red", sparking a wild car chase that ended in her running over the other woman and shattering her leg.
Browne, 40, became enraged when she spotted her then-boyfriend Ross Perrys with Maria Tigler at his house in suburban Clayton on April 3 and went after them in her car.
At dangerous speeds, Browne pursued another car containing Mr Perrys and Ms Tigler around the neighbourhood, ramming them before they stopped and got out.
But Browne kept driving, taking aim at Mr Perrys and Ms Tigler as they ran away on Viney Street in Clarinda.
"She has then hit Ms Tigler with the car, causing parts of her body to go under the car," prosecutor Megan Casey told the County Court on Thursday.
"Ms Tigler heard her bones breaking from being hit. She was dragged about 30 metres."
Browne pleaded guilty to recklessly causing serious injury to Ms Tigler.
She told police she "saw red" and was "angry and jealous".
"She had her suspicions they were seeing each other and they were confirmed," Ms Casey said.
Judge Frank Gucciardo accepts the crime was driven by jealousy, stemming from Mr Perrys's "betrayal".
But it was no excuse for Browne's actions, which put the community in danger as well as Ms Tigler's life.
"Jealousy is a beast," he told Browne's plea hearing.
"She's lucky not to have killed (Ms Tigler). That's the bottom line."
Ms Tigler suffered a fractured femur and needed a titanium rod inserted in her thigh.
She also needed treatment for a broken ankle, and suffers flashbacks and nightmares.
"She is still limping and probably will be forever," Judge Gucciardo said.
Browne, who has already served nearly 200 days in custody, will be sentenced on October 26.
Defence lawyer Matthew Page urged the judge to consider Browne's tough life, including bringing up her autistic son mostly alone.
"She's done a pretty good job because her son is now 21 and studying accounting," he said.