Caroline Benson-Luscombe, 44, shares her true life story:
I stood at the school gates and joined in the usual chatter with the other mums.
“I think my little boy’s coming down with something,” one mum, Sarah*, sighed. “He’s definitely not himself.”
“Sounds like that bug that’s been going around,” I said, as she reeled off the symptoms.
A lot of the parents came to me for advice because I worked as a nurse, and I was always happy to help.
The town we lived in was small – everyone knew each other.
My son Rhys, six, was in the same class as Sarah’s boy, and my hubby Greg was Sarah’s martial arts instructor.
I wouldn’t exactly say Sarah and I were good friends, but we always had a chat as we waited outside the classroom.
When I got home that day, Greg was waiting for me.
He’d just gotten back from his usual three nights working away as an aircraft engineer.
We’d met when we were just 16, and after 19 years of marriage and two children, we were as happy as ever.
“We missed you,” I told him, as the kids ran through the door to hug him.
A few weeks later, I received a text. It was from a number I didn’t know.
You need to open your eyes, it read.
Keep a watch on your husband.
I showed it to Greg.
He seemed as confused as I was.
“Probably just someone trying to stir up trouble,” he said.
But then one day I was on the computer when a hotel receipt popped up in our emails.
It was for a cheap hotel in a nearby town. And it was in Sarah’s name!
I knew the martial arts team had a tournament coming up in that town, but why did Greg have Sarah’s paperwork?
“She wanted to check she had the right hotel so she emailed me the receipt,” Greg explained when I asked him so I let it go.
But a few weeks later, I stumbled across something else on the computer that took my breath away.
It was a photo of Sarah wearing a bodice and suspenders!
I knew then they had to be sleeping with each other.
“What the hell is this?” I demanded when he got home.
“It was just a joke,” he said. “Sarah’s friend sent it to me as a prank to embarrass her.”
It sounded so far-fetched, but Greg didn’t seem flustered.
We’d been together so long and I’d never worried about what he was up to before.
So I decided to give him the benefit of the doubt.
A few days later, Sarah’s husband Jim turned up at the house.
“I have proof your husband is sleeping with my wife,” he said.
But Greg quickly swooped in.
“We’re just friends,” he said. “I’m sick of everyone saying otherwise.”
“I’ve seen emails between you!” Jim said.
He even had his laptop with him, but Greg wouldn’t let him in the house.
Jim left and once again Greg insisted nothing was going on.
But I was finding it harder and harder to believe him.
That night I tossed and turned in bed.
I was in turmoil.
I was exhausted and puffy-eyed the next morning, but I managed to drive the kids to school as usual.
When I saw Sarah, my blood boiled.
“What a tangled web we weave,” I said loudly.
Sarah looked flustered.
After I’d taken the kids into school, I came outside to find her showing another woman texts Greg had sent her.
“You need to get your husband down here now,” the other woman said.
I called Greg and he arrived soon after. He looked from Sarah to me and his expression suddenly changed.
“Okay, something did happen,” he said. “But it’s over now.”
Hearing him admit it was devastating, but I kept it together, determined no-one would see me cry.
“I want you out of my house,” I said to Greg.
For the following week, I was in pieces.
Greg stayed at his mum’s and kept phoning, begging me to take him back.
“It was a huge mistake,” Greg said. “Please, Caroline. I want my family back. I love you.”
I felt sick when I thought about what he’d done, but I was so distraught that I didn’t have the strength to argue.
I decided to take him back for the sake of the kids.
It was tense between us at first, and I saw Sarah nearly every day at the school gates, which made things harder.
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I just wanted to somehow keep my family together.
But the trust was completely shattered. Soon I was sure Greg was seeing her again.
When I confronted him, he confessed.
“I love you both,” he said, head in his hands. “I just don’t know what to do.”
“You don’t have to choose,” I said. “I won’t be second best.”
I asked Greg to leave.
Later, he admitted Sarah was pregnant with his baby.
A year later we got divorced, and they married and moved away.
I struggled to move on, and the kids struggled to forgive their dad.
Now, I’m feeling stronger.
I was so blinded by love that I couldn’t see the truth – but I know I will never make the same mistake again.