Betty Friedan, whose manifesto "The Feminine Mystique" became a best seller in the 1960s and laid the groundwork for the modern feminist movement, died Saturday, her birthday. She was 85. Friedan died at her home of congestive heart failure, according to a cousin, Emily Bazelon. Friedan's assertion in her 1963 best seller that having a husband and babies was not everything and that women should aspire to separate identities as individuals, was highly unusual, if not revolutionary, just after the baby and suburban booms of the Eisenhower era. Friedan, born February 4, 1921, in Peoria, Illinois, was a high achieving Jewish outsider growing up in middle America. Her father, Harry Goldstein, owned a jewelry store; her mother, Miriam, quit a job as a newspaper women's page editor to become a housewife.