The singer recently announced she is embarking on a tour of North America in the summer, which will be called Last Girl on Earth. She came up with the title as that is how she tries to live her life. Rihanna claims too many people get caught up in thinking about what others want, which means they are never happy. She is adamant she only considers herself when weighing up opportunities, as she is terrified of looking back on her life and having regrets. "I like to think about myself as the last girl on earth because sometimes people make decisions based on the outlook of others and, you know, to me, my life is my life," she explained. "It`s my world, and I`m going to live it the way I want to. That`s how I think about everything, that way I`m focused on me, and my work. It`s a really narrow space, a focus." Rihanna performed on talent programme American Idol earlier this week, and admitted she was nervous before taking to the stage. She didn’t have much time to prepare for the live performance, explaining she is spending all her time working on the tour plans. "It`s my first time performing on Idol and it`s a little nerve-wracking because we`re in the middle of our tour rehearsals and it`s a really time-demanding experience and we just had to fit this in there," she told ET Online. Ke$ha will support Rihanna for the series of show. Rapper Nicki Minaj was also due to take to the stage, but she has pulled out after deciding she wants to spend more time working on her album. "Barbz I`m sorry 2 say I will not be going out on RiRi`s tour. I`ve decided 2 use that time 4 the completion of my album. Hope u understand," she wrote on her Twitter page. "Thx 4 understanding. And Thanks to Rihanna 4 being a sweetheart and extending this great opportunity 2 me. Support the show! Luv, HB (sic)."