Diane Fay Finn was born on December 6, 1928 in Boston, Massachusetts to Henry Michael Finn, a merchant, and Bessie Ruth Finn. She attended Girl's Latin School Boston, Massachusetts from 1940-1946 and then went to Mount Holyoke College from 1946-1950, receiving a B.A. in political science. On June 26, 1949 she married Matthew Nathaniel Sherman and they had three children. In the mid-1990s, she married Robert J. Levine.