Bear had suggested that Lillie had been unfaithful during an appearance on Loose Women where he claimed his 'past two girlfriends had cheated on him' and later tweeted, accusing Lillie of cheating with Ex On The Beach star Ross Worswick.
Lillie, meanwhile, categorically denied there is any truth in Bear's allegations - which Bear himself has now confirmed, after speaking to Ross and learning "nothing happened" between him and Lillie.
Taking to Twitter, Bear corrected himself and told Lillie he was sorry. He tweeted: "Never believe rumours .. Just spoke to @rossworswick and nothing happened .. Sorry @LillieGregg I wish you all the best of luck."
Lillie didn't directly respond to Bear, but she did re-tweet his message. She also liked another tweet posted by a fan that read: "@stephen_bear @rossworswick @LillieGregg At least you were big enough to apologise! But maybe should of checked before posting on here."
Ross, meanwhile, hasn't commented on social media.
Bear first alleged that Lillie had been 'unfaithful' while discussing his past relationships on Loose Women. He admitted to Katie Price that he had been hurt before and claimed: "The past two girls I've been with in my life, they've cheated on me and it's bang out of order. I'm getting labelled a cheat and this and that, no.
"Unfortunately, the last two birds I've been with did the dirty on me. The next girlfriend I do have, I'll still treat them as well as I did them, but hopefully it works out and I get married."
While he never mentioned Lillie's name, he did later directly tweet about her and said: "Had a suspicion about @LillieGregg .. She jumped into bed with @rossworswick while I was seeing her .... #ruthless #justfoundout."
Bear has since deleted his initial tweet.
Wow how dare you..Quite happy to go to the extent of a lie detector test on this one. Theres only one cheat and it certainly wasn't me.— Lillie Lexie Gregg (@LillieGregg) August 30, 2016
Categorically not true. That is my only comment.— Lillie Lexie Gregg (@LillieGregg) August 30, 2016
Lillie took to her own Twitter page to deny Bear's accusations. She tweeted: "Wow how dare you..Quite happy to go to the extent of a lie detector test on this one. Theres only one cheat and it certainly wasn't me."
In a second tweet she added: "Categorically not true. That is my only comment."
A rep for Lillie also denied there is any truth in Bear's claims when contacted by Reveal.
Bear and Lillie initially met while filming for Ex On The Beach's fifth series back in April. A month later they went public with their romance, and were dating when Bear entered the CBB house.
Their relationship, however, broke down while he was on the show, as Bear declared he wanted to be single again. He appeared to dump Lillie onscreen, telling his housemates he 'doesn't have time' for a girlfriend, and doesn't think Lillie is 'the one' anymore.
Bear publicly moved on with his housemate Chloe Khan, prompting Lillie to enter the house and confront Bear over his behaviour. She told him she had been "embarrassed and humiliated him."
Following her appearance, Bear broke down in tears and told Big Brother he thinks Lillie has had a "lucky escape" from him.
Since winning the show, Bear has claimed Chloe is the only girl he is now interested in.
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