Corryn Rayney had shared wine by candlelight with a male friend while her husband Lloyd Rayney was overseas for work, a relative told police days after her disappearance.
Mr Rayney’s sister, Raelene Johnston, testified this week in her brother Lloyd's wilful murder trial.
Today, her police statement, which she made on August 11 2007 - four days after Mrs Rayney’s disappearance - was made available.
Mr Rayney, a father-of-two, has pleaded not guilty and is fighting an allegation he killed his wife at the family home after their marriage soured and buried her in Kings Park.
In Ms Johnston’s statement, she recalled first meeting the male friend, whose name is suppressed, at the Rayney household while Mrs Rayney was packing to visit Mr Rayney who was on a working stint in 2003.
"(The man) did not seem like the sort of person that Corryn would ordinarily be friends with," she told police.
"Corryn used to be very conservative and he did not seem to be."
"On another occasion, My Mum and Dad went to visit Corryn and the girls while Lloyd was in Bermuda," she stated.
"When they got there Corryn answered the door... they saw (the male friend) sitting at the table in the rear veranda. There were lit candles on the table and wine glasses on the table."
Close friends of Mrs Rayney have told the Supreme Court that they do not believe the mother-of-two was having an affair and simply had a friendship with the man, who was a parent from the same private school as the Rayney children.
Mr Rayney’s defence lawyers have suggested the relationship was more than a friendship.
Mrs Rayney was last seen alive at an evening boot scooting class, with witnesses testifying that her husband -who slept in a separate bedroom -claimed he had not seen her after the dance class.
In her statement, Ms Johnston described how she and her brother had called friends and contacts to try to find the missing 44-year-old after she failed to show at work the next day.
She said she had offered to call a certain man because she was aware of "incidents where (the man) has been aggressive to Lloyd".
The statement, which had been edited by the court to remove the man's name, did not make it clear whether the person Ms Johnston was referring to was the male friend of Mrs Rayney.