To celebrate the launch of TIME’s new multimedia project – 100 Photographs: The Most Influential Images of All Time – we asked leaders in a number of fields, from technology to the arts to business, to share the single photograph that most influenced their lives. Purchase the 100 Photographs book now.

In the mid-1930s, my brilliant great-grandmother, Margaret Yardley Potter, almost got a divorce and almost moved to Europe in order to reinvent herself. This was the passport photo she had taken, right after she walked out on her unhappy marriage. Here she sits with her beautiful 16-year-old daughter (my future grandmother), ready to set off together on a journey that never happened. For some reason, Margaret went back to her husband. She stayed with him until she drank herself to an early death. This photo haunts me. My great-grandmother missed her one chance at liberation. Maybe the social climate was wrong for it. Seventy years later, I did get the chance to divorce myself from unhappiness and sail away, reinventing myself after a failed marriage. I embarked on this journey for me, and for her, too. Sometimes it takes a long time for a woman’s promise to finally become realized.

Elizabeth Gilbert is the best-selling author of Eat, Pray, Love and six other works of fiction and nonfiction.