Dorfman, 28, tells People she has been working on the project - which she describes as an anti-self-help book - since she relocated from Atlanta to New York City.
"I feel like we, as women, don't share a lot of bad emotions that are associated with breakups, and this book kind of defies that," she tells People. "I did every good, bad, ugly, sad, crazy, psychotic thing that women do. I'm like, here it is - we all do it. I am proof that we all do it."
Murray, a former professional baseball player, won Dorfman's heart on the show and the couple got engaged in 2014. They called off their engagement in January.
Dorfman's book, It's Not Okay, is scheduled to hit shelves next spring. Will you read it?
VIDEO: Watch our interview with Andi and Josh in happier times