Anthea Turner has said she monitored her ex-husband’s satnav and even tracked his bike rides when she suspected he was being unfaithful.
The TV presenter, 56, was married to Grant Bovey until 2015, when she was granted a divorce on the grounds of his adultery.
The couple first split up in 2012 but briefly reconciled before separating for good in August 2013.
Writing in the Mail On Sunday, Turner said she became suspicious something was wrong when Bovey was angry that she spoke to the press about how happy she was to have reunited with him at the end of 2012.
She wrote: “Instead of sharing my happiness, he went ballistic, ranting and raving about discussing our private life. I couldn’t understand where all this anger had come from.
I had my suspicions, but were they justified – or plain paranoia? There was only one way to find out. It was time to turn detective.”
She said she started checking his emails to see if he had been where he said he was, before checking his car’s satnav.
She added: “Grant has always enjoyed cycling but all of a sudden, he began announcing plans to cycle to all sorts of strange places.
“He has an electronic device on his bike which plugs into a home computer and logs routes and mileage, yet when I looked he hadn’t been anywhere he claimed to have been.”
Turner said she even checked the history of the anti-theft tracking device on their cars, writing: “It was time to move things up a gear.
“I became a regular Miss Marple, logging on to the computer to check journeys he made, credit cards he’d used and text messages he’d sent.
“Grant had no idea I could even do these things. As far as he was concerned, I was a technophobe, unable to carry out the simplest tasks on a computer.”
The couple married in 2000 after first meeting in 1998, when they were both married to other people, but Turner said she never saw Bovey’s infidelity coming.
She said: “We didn’t end our marriages lightly; ours was never simply a casual affair. But, inevitably, breaking up two homes had painful consequences.
“Many mistakes were made and people were hurt, something I’ve apologised for many times and something I would walk over broken glass to avoid happening ever again.
“Even so, I never saw Grant’s adultery coming. Call me naive, but infidelity had been last on my long list of scenarios to explain Grant’s behaviour when his affair first began in 2012.”
Turner has now penned a book for women going through similar situations, How To Survive Divorce, which she hopes will help people like her.