Rush was born to Ashkenazi Russian-Jewish immigrants in Manhattan and grew up in The Bronx before moving to New Rochelle, New York. In "Growing Up Molested", the preface to her book The Best Kept Secret, Rush wrote that she "painfully remembered that I, despite the amenities of a middle-class upbringing, had also been sexually abused as a child." Rush's parents had fled a small town in Czarist Russia because her father was facing forced conscription into the Russian Army, as well as for reasons of antisemitism and poverty. Her family observed Shabbat and her parents worked in sweatshops on the Lower East Side until her father graduated from Brooklyn College and opened a drugstore. She subsequently moved to Manhattan's Greenwich Village in the early 1970s. She was married to Bernard Rush and is survived by son, Thomas, his two children, and daughter, Eleanor. In 2005, she was honored with the New York City NOW Chapter’s Susan B. Anthony Award to grassroots feminists.
