The former TOWIE star was comforted by housemate Edele Lynch as she recalled a past relationship and confessed she was still in love with the unnamed man.
Lauren, 28, didn't name who she was talking about.
She told Edele: "Today, I thought of my ex and thought, 'F**k, what have I done?' I know he has a bad record but he ain't that guy anymore.
"When he was in my life he would never have anyone say a bad word about me."
Lauren appeared concerned her ex may have heard things she'd said about him in the house, lamenting: "I completely f**ked it up."
She then began to cry as she told Edele: "I'm trying to cover it up."
When Edele asked if Lauren was trying to cover up the fact she still loved her ex, she replied: "Yes. I love him. I don't think I'm over it. I think I am but I'm not…"
The episode ended with Edele trying to console a weeping Lauren.
Lauren didn't specifically name the ex-boyfriend she was talking about, meaning there has been plenty of speculation online about who it is. She dated ex-TOWIE co-star Mark Wright for ten years but most recently had a two-year relationship with Jake McLean.
Celebrity Big Brother airs nightly on Channel 5.
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