He was charged with murdering the woman and the attempted murder of her husband.
He appeared in the Waitakere District Court yesterday, where extensive suppression orders were made preventing the publication of the alleged killer and victims' names.
His lawyer, Sheila McCabe, told the court he had "serious mental health issues".
Judge Hemi Taumaunu described the incident as "tragic and disturbing" and remanded the man in custody to appear later this month before the High Court at Auckland. He will be held at the Mason Clinic so mental health reports can be completed.
The dead woman worked as a sales representative.
Her managing director paid tribute to her yesterday. "We are deeply saddened by the loss of our much-loved colleague," she said. "She was a very special member of our team and will be sadly missed." Her husband works as a consultant, and is the director of several companies.
His friend and former business partner was reeling over what had happened to the couple.
"She was a wonderful person, a fantastic person," he said of the dead woman.
"She was a really loving mother. This is just a tragedy. They were a great couple... I'm still in shock."
- additional reporting APNZ