In her 40s, Phelps broke convention again when she married a man 17 years her junior. Later in life she urged women to burn their corsets. Her later writing focused on feminine ideals and women's financial dependence on men in marriage. She was the first woman to present a lecture series at Boston University. During her lifetime she was the author of 57 volumes of fiction, poetry and essays. In all of these works, she challenged the prevailing view that woman's place and fulfilment resided in the home. Instead, Phelps' work depicted women as succeeding in nontraditional careers as physicians, ministers, and artists.