Meta Fuller was born on February 7, 1880, at San Francisco, California, daughter of William and Mary (Eaton) Fuller, a descendant of one of the First Families of Virginia. One October 18, 1900, she married Upton Beall Sinclair, socialist writer best known for the exposé on Chicago meat packing plants, The Jungle (1906). Together they had one child, a son, David, born December 1, 1901. After the sale of The Jungle, Sinclair set up a communal living experiment called Helicon Hall in New Jersey; it burned down in 1907, leaving the family impoverished and causing Fuller to be sent to the sanitarium at Battle Creek. Both Sinclair and Fuller had extramarital affairs, and in 1911 Fuller left Sinclair for Sinclair's friend, "Tramp Poet" Harry Kemp.

On January 9, 1916, Fuller married Lester Keene in New York City, and together they had one son, Lester. The couple moved to Florida in 1932 and lived at Coral Gables until 1934 when they removed to St. Petersburg, where Lester Keene died on February 12, 1947. She remarried on August 18, 1947 in Newport, Tennessee to John A. Stone.

Fuller was a member of the National Association of American Pen Women. She served five years as president of the Poets League and later president of the Poetry League in St. Petersburg. She died on September 3, 1964 in St. Petersburg.