Durban - Jane Govindasamy had confessed to her boss on the day of her murder that she had been involved in an extra-marital affair with Colin Pillay.
Pillay is accused of killing Jane and her two daughters Nikita and Denisha in September 2018.
Testifying in the Durban High Court on Wednesday Shaylin Pillay, an operations manager at the company where the victim works, said Jane had introduced Colin as her husband.
He said she had told him that Sagren Govindasamy was in fact Colin's brother.
Pillay told the court that Colin Pillay even attended their boss' 50th birthday party in June 2018.
He said Pillay had arrived at the party driving a tow truck and Jane refused to allow him to drink alcohol.
Pillay said on September 20, the day she was murdered, she had confessed to him that she was involved in an affair with Colin, and that Sagren was in fact her husband.
The trial is currently in its third week and is expected to continue until next week.
Warrant Officer Bob Pillay from Provincial Organised Crime is currently in the witness box. He arrested Pillay two days after the murder.
Murder accused Colin Pillay who has pleaded not guilty to three charges of murder and theft is expected to take the witness stand later today.