This afternoon, Channel 5 announced that Brian decided to walk after nearly two weeks in the house.
The reason behind his departure has yet to be revealed, but it has been speculated that Brian quit the show following another row with Helen Wood.
In a new video on the Big Brother website, while being comforted by Nick, Nikki said: "At least no one's going to make him cry on the outside. I feel like I let him down."
Last night, Brian came to blows with Helen once again. Things turned nasty between the pair after a fun group task, and Brian blasted Helen for her attitude in the house.
Brian also said that he had been avoiding going anywhere near Helen and Marc O'Neill.
"Yes I've been quieter than normally because I cannot be myself in here," said Brian. "The pair of you make me feel about this big. You tag team consistently, you're [Helen] the horrible cheerleader and you're [Marc] the meat head jock."
Brian entered the house almost two weeks ago along with Nikki and Helen as part of a secret task, that saw them live in a bunker next door to the main house with Marc, where they watched housemates' every move.
The group then moved into the main house 48 hours later, but Brian and Helen have been embroiled in arguments ever since.
Last week, Brian threatened to quit after an argument with Helen, where he called her "thoughtless and heartless".
Brian, who won Big Brother in 2007, said: "I want to leave. I don't want to be in this house with Helen and Marc. They're vile human beings. I don't want my Big Brother memory to end with walking up those stairs with her. Sometimes you have to stand by your convictions."
Big Brother persuaded him to stay but it seems like this time round, Brian stuck to his word and walked.
Find out about Brian's exit at 10pm on Channel 5.
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