Charlie is an ambitious and dedicated doctor who is loving toward his family and friends. The novel’s earliest depiction of Charlie is as a fun-loving and down-to-earth college student who quickly connects with Garrett upon their first interaction. He is immediately indebted to Garrett when Garrett rescues him from being struck by a car and takes him to the hospital for treatment. This moment solidifies Charlie’s trust in Garrett and his love for him, and Charlie returns to this moment in his mind as he ages. Likewise, the bond between Charlie and his brothers and their parents is a strong one rooted in unconditional support. 

Throughout the novel, Charlie is defined and shaped by his love for Cece and by the heartbreak that rules his life after she ends their relationship. The novel gives no evidence that Charlie is harsh or bitter toward Cece or Garrett; instead, he strives to live out a meaningful and fulfilling life by entering into new relationships and raising children. In the years that immediately follow their breakup, Charlie is eager to prove to Cece that he is superior to Garrett, hoping that she will regret what she has given up. This ploy is merely an act, however, and in truth, Charlie remains in love with Cece. This love is genuine, and Charlie cannot help but want the best for Cece, demonstrating that his love for her is unconditional, despite the hurt he has suffered. 

In the same way, Charlie’s loyalty toward Garrett remains unfailing. Though Cece and Garrett have hurt him deeply, Charlie continues to cultivate his friendship with both. Charlie shows the same commitment to his son, Jasper, repeatedly seeking help for him for his drug addiction despite Jasper repeatedly pushing him away. Charlie is criticized at times for these unfailing commitments, regarded as someone who allows others to take advantage of his kindness. Indeed, his need to have both Cece and Garrett in his life is evidence of Charlie’s loneliness and of his deep desire to forge meaningful connections. In the end, Charlie is able to find peace, accepting the way that life without a marriage to Cece has unfolded and forgiving Garrett.

Garrett’s character evolves as he is forced to change many of his central beliefs throughout the novel. When the novel opens, he is a young 20-something who is pessimistic about the future and who deals with depression. The guilt that he harbors over the death of his college friend Elias led to a mental health crisis for which Garrett was hospitalized and then diagnosed with depressive psychosis. Garrett finds it difficult to connect emotionally with other people and therefore isolates himself, communicating only with his dying father. He is passionate about the Montana ecosystem and grief-stricken by climate change and environmental destruction. He identifies very deeply with the landscape and feels most at peace when he is physically outside in it. When he falls in love with Cece, Garrett is dramatically transformed. Even as he admits to himself that he is falling in love with her, Garrett berates himself, certain that he is unworthy of love from anyone so engaged with life and living as Cece is. Cece’s mutual feelings for him, however, cause Garrett to rapidly change: He feels alive again—that is, he shifts from being consumed by depression to having a positive outlook on the future.

This shift causes Garrett to work to better his life in other ways: He completes his education, which leads to him successfully pursuing a profession in conservation. The work that Garrett performs in the field consumes him in a positive way, providing him with a sense of purpose that he did not have previously. This work, however, also takes him away from Cece and their daughter quite frequently. As a result, as Garrett ages, he finds it increasingly difficult to connect to Cece. In a similar way, he continues to harbor feelings of guilt and shame for betraying Charlie by marrying Cece. Garrett maintains his friendship with Charlie, largely because Charlie is the one who makes a concerted effort to spend time with Garrett, but there is a palpable wedge between them. Not only does Garrett feel responsible for the death of their mutual best friend, Elias—despite Charlie’s insistence that Garrett is not to blame—but he also feels as though he has permanently hurt Charlie. It is only as he enters his seventies that Garrett achieves peace in both respects: He reconnects with Cece (even though her dementia means that she often can’t remember his name) and is able to move on from the past.