Strayed was in a self-destructive spiral, sleeping around and cheating on her husband, getting divorced despite still loving him, shooting heroin, grieving the loss of her mother four years before, and crushed by the realization that her siblings and step-father had no interest in maintaining the family connections that were so important to her when she decided to hike the Pacific Crest Trail alone as an attempt to find her center and to become the person she really wanted to be. Being out in the wild nature of the trail offered her a way to be with herself without all the noise and distraction of the world butting in on her. It is this solitude that she craves in order to take an honest look at her life.
So she sets out, completely and woefully unprepared for the rigors and reality of a hike of the magnitude she's chosen. Thanks to the chance encounters with kind and giving people on the trail, she does make it though. Her account of her time on the trail is peppered with flashbacks to her pre-hike life, to the grief she still carries, heavy as the oversized pack on her back. These insights into the events that drove her onto the trail do mean that there's not as much about the hike itself or nature as might be expected but then this isn't really a hiking memoir so much as it is about getting to the core of who she was as a person.
Written from the perspective of twenty years on from the hike, it is interesting what Strayed has chosen to include. She is brutally honest about her many mistakes and she offers up raw emotion for sure. But she is strangely concerned with how she looks (her lost toenails, poor blistered and abused feet, scaly skin on her hips, ratty hair, grubby and unwashed appearance) whenever she has one of her chance encounters with other hikers or people in the towns she has come down to and whether or not she will have sex with selected folks, returning to these concerns again and again. She clearly remembers the kindness of others who save her from herself and her poor planning, time after time, and the luck that saves her just as frequently. She does face real challenges, both physical and mental, and overcomes them as she gets back to the basics of survival and pure existence but she isn't as alone in this overcoming as she had intended. The backstory at the beginning of the book is rather slow going, albeit generally necessary, and not as engaging as her struggles, dogged perseverance, and soul searching on the trail, so the narrative is unevenly paced and the ending is extremely rushed.
Strayed apparently did come to some peace with the loss of her mother and with her past through her hike but most of that peace seems to be a simple acceptance of who she is rather than anything more insightful or profound than that. She hasn't really changed, just come to love herself as she already is, which is a bit problematic given the destructive, poor choices that lead her to the trail in the first place. The book was a generally engaging read despite these problems and although it should be a caution against following in her footsteps rather than an endorsement, it does also show that nature can in fact heal us and help us center ourselves in ways that our chaotic, babble-ridden world cannot.