Writing in her column for New magazine, the Celebrity Big Brother winner revealed that Reid warned her the split is about to get "ugly".
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"I feel like I'm having the worst time of my life, but I'm lucky to have a lot of support. Everything happened at once - the rat in the house, the move falling through, the situation with Alex," she said.
"I have to keep thinking, 'I'm going to get through this'. And I know I will. It's just sad more than anything. When Alex discovered I'd done an interview to defend myself against his accusations, he said to me, 'Now it's going to get ugly'.
"I feel such an idiot. All those months, I think I was in denial. I was having sleepless nights, had milk leaking from my boobs and thought that my partner loved me, but I don't think he ever truly did."
Houghton previously confessed she was "gutted" Reid had given an interview about their split. She dumped him last month, just three months after the birth of their daughter Dolly.
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