Katy Perry is getting on with her life in the wake of her separation from actor Russell Brand. The 27-year-old singer hosted the GiveLove charity benefit at the opening of 1 Oak nightclub in Las Vegas. Perry tweeted about the charity, which benefits Haiti, writing, “Happy to be supporting my best friend @MDMOLINARI & his j.molinari jewelry w/all my other besties in #VEGAS for a great cause @GiveLoveOrg.” It is her first official U.S. appearance since 36-year-old Brand filed divorce papers and ended their marriage.The former couple was married for 14 months, and in that period showed themselves to be in a committed and stable relationship. Perry is best known for her music with hit songs such as, “I Kissed A Girl” and “California Girls.” Brand is known for being a comedian, singer, actor, author, and for his history of sex and substance abuse. Brand is now sober and has starred in Forgetting Sarah Marshall and Get Him to the Greek.