The 36-year-old revealed to the High Court that she and her husband had temporarily split while she was pregnant with their fourth child, Cass, following his drink-driving arrest in 2017, which saw him caught with another woman in the car.
WATCH: Rebekah Vardy cries in witness box during Wagatha Christie trial
Coleen admitted that she began her social media sting operation after a photo showing Wayne posing in bed at their family home during their marriage crisis was leaked to The Sun newspaper.
"I was in a vulnerable situation. There had been some wrongdoing by my husband," the mum-of-four told the court. "I was spending a lot of time at my parents' house. I didn't know how my marriage was going to work out. Me and Wayne were trying to figure out our relationship and where we were going."
She added: "But I didn't want people to know that... I hadn't settled on 'This is it, we are getting back together.'"
Coleen and Wayne briefly separated in 2017
Coleen said the leak was a personal betrayal as it implied they had worked through their problems following Wayne's arrest in Cheshire.
The former footballer admitted he "made a mistake" after he was caught by police driving single mum Laura Simpson's car, with her in the passenger seat, while he was under the influence.
Rebekah has denied Coleen's allegations
Those series of events led Coleen to plant fake stories on her private Instagram, some of which then appeared in The Sun, with her later revealing she had blocked all her followers apart from Rebekah Vardy, who she accused of leaking her personal information.
Coleen was then dubbed 'Wagatha Christie' after her post on Twitter went viral in 2019. Rebekah, who is married to professional footballer Jamie Vardy, denied the accusation and is suing Coleen for libel. The trial continues.
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