Andrew Watson, originally from Edinburgh, was arrested in Canada by detectives probing the disappearance of Lise Fredette, whose body has never been found.
The Peterborough Superior Court of Justice in Ontario heard Miss Fredette, 74, called in police to complain that Watson had been stalkiing her.
Detective Constable Ian Maxwell went to Watson’s house in Peterborough September and November 2014 to tell him to leave her alone.
Watson, 78, was arrested ten days after Ms Fredette was last seen leaving her job at Walmart on November 12, 2014. Her glasses and keys were found next to her car at home and there was blood in her driveway.
The court also heard from Cathy Robinson, who worked with Ms Fredette in the kitchen of a local dance hall.
She said the dance on November 8, 2014, was the last one Ms Fredette attended before she went missing.
The retired nurse said Ms Fredette told her about a Scottish man named Andy she’d dated that was “very controlling”. She said: “She was different that night. She was very frightful.
Watson denies first-degree murder and criminal harassment. The trial continues.