Lesley Crewe was born and raised in Montreal, Quebec. After completing her education at Concordia University with a degree in English and Education, she moved to Homeville, Cape Breton with her husband. Together, they raised a family in this new location.
In the early 2000s, Crewe began her writing career as a features writer and columnist for Cape Bretoner Magazine, where she wrote "Home Fires" until 2005. She then became a columnist for the online magazine, Cahoots, where she wrote "Lesley's Letters" from 2005 to 2009. Crewe's writing talent was recognized in 2005 when her first novel, "Relative Happiness," was published by Vagrant Press, the fiction imprint of Nimbus Publishing. The novel was a bestseller and was even shortlisted for the Margaret and John Savage First Book Award. Since then, Crewe has written a total of ten novels.
In 2012, "Relative Happiness" was optioned for film, and in 2014, the movie was released. It was produced by Wreckhouse Productions, directed by Deanne Foley, and featured Australian actress Melissa Bergland, as well as Canadian talents like Susan Kent, Jonathan Torrens, and Rob Wells. The movie brought Crewe's characters to life on the big screen and showcased her storytelling abilities to a wider audience.