The Ex On The Beach star, 25, entered the house on Thursday (18 August) as part of the shopping task, which required housemates to complete simple challenges without being distracted by things including familiar faces.
Lillie entered while fellow EOTB star Bear, 26, was balancing three doughnuts on his head, telling him she was "humiliated and embarrassed" that he'd dumped her on TV and hooked up with housemate Chloe Khan.
Speaking on ITV's This Morning, Rylan said: "We found it very, very hard to even get [Lillie]. I think she was supposed to be coming in today [to This Morning] to talk about it and hasn't done that.
"We tried really, really hard to get her. We wanted to get her in earlier because we were going to do this task a little bit sooner but she just said, 'I can't do it, I'm absolutely gutted.' We'd seen a couple of posts on her Twitter and Instagram saying she was devastated. I think one headline said Bear told her he was going in the house to get the money to buy her an engagement ring so you can imagine, this is a woman scorned."
When asked if producers had given Lillie her speech, Rylan, who hosts spinoff show Bit On The Side, said: "No, honest to God, I tell you now."
He added: "She was in the house for about five minutes."
Lillie's entrance absolutely stunned Bear who remained silent as she spoke to him. He stared at the ground and shrugged his shoulders as she poured her heart out, reminding him she'd been with him the day he entered CBB and had supported him throughout.
"The embarrassment and humiliation I've had… this is all one big game to you, it is a joke at my expense," she told Bear, who didn't say one word to her before she left.
They'd been dating just over two months, after meeting while filming Ex On The Beach 5. After telling housemates he wanted to be single, Bear hooked up with Chloe, who was evicted last Friday. She's since said Bear told her to wait for him on the outside.
He faces eviction on Friday night's show against Bear, James Whale, Sam Fox and Ricky Norwood. Two of the housemates will be going home in the first double eviction of the series.
Meanwhile, Lillie tweeted after the episode aired: "Hardest decision to go in the house...It was for closure & that's what I got. Thank you again for all of the kind messages it's appreciated."
CBB airs 9pm on Channel 5.