She wants to have her cake and eat it: look like a morally righteous person and get rid of someone she doesn't like because she knows she's safe after having buddied up with the favourite
http://www.channel4.com/bigbrother/v...c8e51c/play.c4
It is a game but I wish people would keep insisting that it's just because she's a nice person - she's playing the game better than all of them. If this had been Lisa or Karly before she left most people on here would have been saying how much they hate them.