Similarly to Jordan, who recently discovered her hubby, Kieran Hayler, cheated with her best pal, Jane Pountney, Lucy, too, was cheated on with her best friend.
"It was my worst experience," she tells us. "He was my first boyfriend and we dated for five years, between the ages of 15-20.
"I know it sounds young but he was my best friend and my first love - yet the most ridiculous liar.
"He slept with my best friend. They had an affair on the low-down, which was a double betrayal."
After hearing numerous rumours at the time, Lucy, 23, confronted her friend, who repeatedly denied the accusations.
She remembers: "I decided there was only one way to find out the truth – I needed to speak to him.
"I was so distraught that I burst into tears and begged him to tell me the truth.
"He finally admitted over loudspeaker that the rumours were true and they had been sleeping together while we were together.
"The colour literally drained from her face and she started screaming that he was a liar.
"But I could tell from her body language that she was the one lying."
Heartbreakingly, in her new book, The Dating Game, Lucy adds: "I was so miserable for a while.
"I really couldn't understand how someone who loved me could do that to me, and how my best friend could betray me like that."
Lucy Watson's book, The Dating Game, is out now
Read the full interview in this week's Reveal magazine
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