Britney Spears insists she'll have no problems performing songs about her break-up with ex-fiance Jason Trawick when she hits the stage for a two-year residency in Las Vegas in December (13) - because belting them out onstage is therapeutic for her. The Toxic singer will mix up hits and new songs from her upcoming eighth album for the Britney: Piece of Me shows, which begin on 27 December (13) at the Planet Hollywood resort in Sin City - and she has revealed that a handful of the tunes are all about Trawick and the couple's split earlier this year. She says, "It's the most personal album I've ever done. After having a huge break-up this year, I had a lot to say in the studio so it was nice to have a therapy like that and to be able to share that with my fans." And she has no reservations about singing about the broken romance and her heartbreak onstage. She tells U.S. radio host Ryan Seacrest, "Usually the stuff that really comes from the heart is usually the best stuff and has the best beat and really kind of helps you get over the break-up really easy, 'cause you sing about it and have to think about it every night. "You're like, 'It's OK! I'm performing now so it's totally fine. You just get over it and it's like a therapeutic way to get over it."