Last month, a jury convicted Mulvihill, 46, of the stabbing murder of his former mistress Rachelle Yeo at her North Curl Curl unit on July 16, 2012, after she called off their affair.

The father-of-three is facing a lengthy jail term.

In a sentencing hearing in the NSW Supreme Court on Friday, Justice Elizabeth Fullerton said evidence from Mulvihill's ex-wife Celine Carroll of his years-long campaign of terror against her showed he struggled to accept when a relationship was over.

Ms Carroll, who was married to Mulvihill for 18 months in the early 1990s, has told the court how he made death threats, including leaving a "goodbye and good luck" card with a bullet in it at her house.

Ms Carroll said that, on one occasion, Mulvihill turned up unannounced at their former marital home in Holland Park, a suburb in Brisbane, and waved a rifle around.

A couple of years later, Mulvihill was waiting outside the lifts at her secure unit block and, when she came out of the lift, he grabbed her around the neck and said, "We need to talk."

Counsel for Mulvihill, Kate Traill, said her client denied the incidents occurred.

Justice Fullerton said, "Are you asking me to find that she made it up?"

Ms Traill replied, "Yes, your honour."

Mulvihill had admitted to hiding under Ms Carroll's bed one night and jumping out screaming, "I'm going to kill you", when she arrived home with a male friend and her sister.

The hearing continues.