The Celebrity Big Brother winner revealed that she found notes in the couple's bedroom in which Reid had detailed their relationship struggles.
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"I found a book in my bedroom in which Alex had written things down about me. It was points, things that had happened, things I'd said, a compilation of things I'd done," she told OK! magazine.
"It's difficult to find that and not wonder about it. The book scared me. My heart raced really fast. I didn't understand it. There were questions he'd written down in it asking, 'What is a man?' I loved Alex, I loved him so much. He was everything to me. Until I found out the truth.
"One night I looked at Alex's phone, feeling like he and one of his friends were plotting something against me, and I found a text from Alex to this man talking about me.
"Alex asked him, 'Is it time to bon voyage her?' Bon voyage me? I couldn't believe what I was reading. Dolly was 10 weeks old. I'm the mother of his child and had no idea he was plotting this."
She added: "I told him I didn't trust, I hadn't trusted him for a long time. He made me feel paranoid, but when I found that text my fears were confirmed."
Houghton dumped Reid last month, just three months after the birth of their daughter Dolly.
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