Starting at the 118 was the best thing Buck ever did, it gave his life meaning, it made him feel useful and worth something. With that comes challenges with mental health and losing patients and accidents. He signed up for this, they all did, they signed up to be the people who rushed in to help even if there was danger. Everyone had their coping mechanisms some healthy and some not. Buck's unhealthy coping mechanism was practically starving himself and shoving everyone away no mater how much he wanted to ask for help.