He's been full of bravado throughout his stay in the Celebrity Big Brother house.

But Stephen Bear, 26, was reduced to tears in the diary room following the shock arrival of his ex-girlfriend Lillie Lexie Gregg.

In scenes to be aired on Thursday night's show, the controversial housemate can be seen struggling to control his emotions as Big Brother asks him how he's doing.

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The truth hurts: Stephen Bear, 26, was reduced to tears in the diary room following the shock arrival of his ex-girlfriend Lillie Lexie Greig

As Lillie makes her entrance, a shocked Lewis Bloor loudly exclaims, 'Oh my god. It's Lillie'

Lillie tells the housemates, 'I was Stephen's girlfriend', which elicits gasps from the celebrities.

Things soon get even more awkward, with the beauty explaining, 'Obviously, this was like the hardest thing I've ever had to do, to walk in through that door. I just needed to see you and look at you in the eyes.'

Shocked: As Lillie makes her entrance, a shocked Lewis Bloor loudly exclaims, 'Oh my god. It's Lillie'

'I'm having to watch this from home. You had me with you until the car came to collect you; you left me with your family. You asked me to be there when you got home, I was supporting you 100%.'

'The embarrassment and humiliation I've had…this is all one big game to you, it is a joke at my expense.' Bear remains silent, passing the task while as Lillie leaves his housemates tell her that she's beautiful.

Bear is called to the diary room to talk through his feelings, but it soon becomes apparent he's finding the situation difficult.

Uncomfortable: The housemates can barely look as Lillie becomes emotional

Difficult: Lillie calls her appearance 'the hardest thing I've ever had to do'

All too much: Macho Bear takes a deep breath as the realisation of the situation sinks in

'In the long run she would have got hurt a lot more,' the emotional star claims. 'I would have married her!'

'I think about her everyday. I can't be with her; it's not fair on her. I was adamant I wasn't going to get with no one. Everything happens for a reason…she's had a lucky escape from me. It took me 26 years to find someone I care about.'

Later Bear is seen talking to housemate Ricky, who tells him: 'That was serious, and I saw your heart sink. I know that feeling.'

Emotional: Bear breaks down following Lillie's appearance

Bear agrees, telling Ricky: 'It was horrible. I didn't think I'd have to deal with that stuff in here…I'd love to see Chloe again.'

A spokesperson for CBB has told MailOnline that Lillie will be one of many surprise guests to visit the house as part of this week's task.

'This week's two day shopping task will start on Wednesday - shown in Thursday night's episode. To win this week’s shopping task, all the housemates have to do is complete a series of seemingly simple tasks that require extreme concentration to master.'

Look who's here! Lillie gets her revenge on Thursday's episode of Celebrity Big Brother, arriving in the house to surprise her now ex boyfriend Stephen

Surprise! Bear's housemates Katie, Frankie and Aubrey looked just as shocked to see their new house guest

'However, Big Brother will throw in an array of distractions to tempt their eye off of the prize, which will include appearances and messages from family & friends and significant others.'

Bear unceremoniously dumped his girlfriend of several months on air. After indulging in several steamy sessions with Chloe Khan, the lothario explained to his living companions:

Together: Bear had been in a relationship with Lillie for several months before he entered the CBB house three weeks ago

Getting hot in here: The star soon shared some steamy romps with housemate Chloe Khan, before dumping Lillie on TV

'I need to be single! I thought I would be with [Lillie] forever, but after thinking in here, she's not the one.' He added: 'I haven't got time for a girlfriend.'

Lillie - who met Bear whilst filming Ex On The Beach with former flame Gaz Beadle - spoke about her utter humiliation at her now ex boyfriend's outrageous behaviour on the reality show.

She told OK!: 'I’m in shock. I’m gutted, embarrassed, humiliated, but the Bear I’m watching on the television is unrecognisable as my boyfriend. It never even entered my head that I couldn’t trust him.

Going somewhere? Lillie was seen with her suitcase packed ready for her visit earlier on Wednesday

Ready for fireworks: The Ex On The Beach star left her Birmingham home on Wednesday for her trip to the Elstree compound

'We’d even talked about getting engaged and moving in together, planning our future.’

However, the model reveals there is 'no way' she would ever forgive him for his antics. She adds: I can’t imagine ever speaking to him again. His sister Hayley has been in touch.

'She’s upset and apologetic at me having to witness this. She said I deserve more. His family are amazing and I’m sad I won’t see them again.'

Off we go! The blonde beauty got into a car with her large designer suitcase, while dressed for the sunshine in a mini skirt and metallic jacket

Heading down south: A spokesperson for CBB has told MailOnline that Lillie will be one of many surprise guests to visit the house for this week's task

Surprise! Big Brother is planning to 'throw in an array of distractions at the housemates including 'appearances and messages from family & friends and significant others'

As well as Lillie, it's also been revealed Geordie Shore star Sophie Kasaei is set to make a dramatic appearance in the Celebrity Big Brother house on Wednesday, to reunite with her cousin, Marnie Simpson.

An insider has told The Sun online: 'Since Marnie entered the house almost three weeks ago, Sophie has been glued to the show.

'She’s really proud of Marnie, she loves her to pieces, they’re family – but she’s not been as impressed with some of the other stars in there.

'While Marnie is all loved up with Lewis Bloor, Sophie knows what he’s been saying when she’s not around, and she’s got a couple of questions for him.'