Pop superstar Madonna has compared herself to iconic Spanish painter Pablo Picasso, declaring she shares his drive to continue working into her twilight years. The singer?s career has spanned more than 30 years since she released her first album in 1983, and star, who unveiled her most recent album ?Rebel Heart? in March, is adamant she will never retire, just like Picasso, who refused to quit painting in the years preceding his death in 1973 at the age of 91.