South Australian woman jailed for 12 years for trying to kill former partner's girlfriend

A South Australian woman who stalked her former partner's new girlfriend and bludgeoned her with a hammer in a jealous rage has been jailed for 12 years for attempted murder.

Amy Kasehagen broke into 28-year-old Bronson Hayter's Adelaide home in April last year and hit her in the head, inflicting up to 10 blows with the hammer before trying to choke her with a plastic bag.

In the Supreme Court today, Justice David Lovell said the attack was brutal, premeditated and terrifying for the victim who was forced to fight for her life.

He said Kasehagen had gathered together a large amount of "chilling" material about her victim, including a USB device which had recordings of the woman made while she was under surveillance.

The judge said the victim was extremely lucky to have escaped with her life.

"She feels she was hunted down like a rabbit in a spotlight," justice Lovell said.

Kasehagen pleaded guilty to attempted murder and aggravated serious criminal trespass and had been diagnosed with a personality disorder and as a "resentful stalker".

Her psychological issues meant she had little remorse, the court heard.

Justice Lovell jailed the 32-year-old for 12 years with a non-parole period of seven years.