The 40-year-old appeared in the Dunedin District Court yesterday where he was jailed for six years after pleading guilty to wounding with intent to cause grievous bodily harm.
Crown prosecutor Craig Power called the events of June 30 "an extraordinary incident".
It began when Ashby turned up at the woman's home drunk and spoke to her through an open window.
She was in bed at the time and told the defendant he was not supposed to be there when he was intoxicated.
Ashby responded by jumping in through the window and punching the woman repeatedly while she screamed for help and pleaded with him to stop.
The 10 to 15 blows were just the start of the ordeal.
As the woman fled into the hallway, Ashby used steel-cap boots to kick her in the head.
The victim lay with her face down on the ground and her ex-partner grabbed her by the hair, lifted her head up and booted her.
"That was degrading as well as seriously violent," Judge Emma Smith said.
So forceful was Ashby that he pulled out some of the victim's hair, the court heard.
Fearing for her life, the woman fled into the living room where her teenage daughter and parents attempted to thwart the onslaught by restraining the attacker.
Ashby, though, could not be held back.
While the victim cowered on the couch, she said she felt her head snap back with each punch that was landed.
Then Ashby turned his attention to her legs.
As he repeatedly kicked them, the victim said she heard a snap, and as the strikes continued, she felt one leg give way.
The defendant's violence continued even after he realised police were on their way.
He punched the victim until she was unconscious and only then made his escape.
The victim, the court heard, required four surgeries for the compound fracture in her leg within five days, one surgery lasting 10 hours.
Her upper body was heavily bruised and she spent 20 days in hospital.
"On any view it was extreme, it was prolonged, it was repeated, it was gratuitous, it was degrading," said Judge Smith.
While Ashby had a significant criminal history, more recently it had been dominated by dishonesty convictions.
Further back, though, were multiple convictions for violence against women and the defendant had served time behind bars for breaches of protection orders.
The judge also questioned Ashby's remorse after he minimised the seriousness of his offending when interviewed by Probation.
Despite that, she refused to impose a minimum non-parole period as requested by the prosecution.
Where to get help:
• If it's an emergency and you feel that you or someone else is at risk, call 111
• If you've ever experienced sexual assault or abuse and need to talk to someone call the confidential crisis helpline
on: 0800 044 334 or text 4334
• Alternatively contact your local police station
• If you have been abused, remember it's not your fault
