Bosworth was working on her latest project, "Protest Song", at the time of her death. "Protest Song" (Farrar, Straus, & Giroux) is about Paul Robeson's work to create federal anti-lynching legislation, which her father collaborated on, and J. Edgar Hoover's subsequent successful campaign to blacklist Robeson. Similar anti-lynching legislation to that proposed by Robeson and Crum was passed by the U.S. House of Representatives on February 26, 2020. During Bosworth's sophomore year at Sarah Lawrence, her beloved brother Bart Jr. committed suicide at Reed College in Portland, Oregon. This event, and their father's suicide six years later in 1959, would inform Bosworth's work throughout her life. During her first year at Sarah Lawrence, Bosworth eloped with an art student. The marriage turned abusive and was annulled after sixteen months. Bosworth married novelist and playwright Mel Arrighi in 1966; the two collaborated on several projects outside of their individual work. Arrighi died due to cardiac arrest and complications from emphysema on September 17, 1986. In the late 1980s, Bosworth was reintroduced to photographer Tom Palumbo, whom she had met decades earlier when Palumbo had been on staff at "Harper's Bazaar" and "Vogue". Palumbo was then seguing from photography into directing theatre. He and Bosworth worked on a number of plays together for the Actors Studio and Lincoln Center, including a production of "The Seagull" starring Laura Linney as Nina and Tammy Grimes as Arkadina. They married in 2000. Palumbo died due to complications from Lewy Body Dementia on October 13, 2008. After Palumbo's death, Bosworth joined the board of the Lewy Body Dementia Resource Center. Bosworth died on April 2, 2020, at Mount Sinai West hospital in New York City, due to pneumonia and complications from COVID-19, at the age of 86.