Castle has an undergraduate degree in philosophy. Honing her writing skills at The New York Times Media Co., she wrote and produces sixty film scripts before dropping out of New York to pursue a 5-state tennis career. In 1984 she was named Top Business Graduate by "Denver Business Magazine". She also has an MBA degree from the University of Denver. She is now married to an Aspen drop-out and lives in a tree house on the gold coast of Florida.