The adage that “behind every great man stands a great woman” might not hold up every single time. But, in the case of American painter George Condo , it rings true. For three decades, the art star benefited from the support and second opinion of his wife Anna Condo , a multidisciplinary artist who studied music, dance, theater, and art while growing up in France. Now, Condo is gearing up for her first single-owner auction of her former husband’s paintings, drawings, and sculptures—none of which have ever been exhibited or sold. They’ll hit the block at Christie’s Post-War and Contemporary Art day sale, concluding its Spring Marquee Week, on May 21. “After his exhibition at the Musée d’Art Moderne de Paris [this winter], it felt like the right moment for New York to see more of George’s early works,” Condo told me over text.…