Tonight, the Big Brother Housemates get to let their hair down during their first Saturday Night Party, which will probably come as something of a relief after the week they’ve had: the excitement of entering the House, the emotional strain of sharing deep, personal stories, losing the Wager Task – it’s all taken its toll. The week also started with all of the Housemates looking like they were just the very best of friends, but time has brought about some divisions in the group – not surprising considering the considerably varied background the Housemates have. They can’t be expected to always…