In Russell Banks's The Sweet Hereafter, one major difference between the two characters Billy Ansel and Mitchell Stephens concerns the ways in which they act and their driving motivations.
Billy Ansel is the father of a pair of twin girls he lost in the bus accident, but even before that, he suffered many losses. He has most recently lost his wife to cancer, and he is even a veteran of the Vietnam War, where he witnessed unspeakable numbers of losses. As a Vietnam War veteran, he has come to accept the inevitability of death, which makes him silent when lawyer Mitchell Stephens from New York City comes to the mountain town to pursue a lawsuit. All of his losses have also driven him to become an alcoholic. Since he was following the school bus in his truck as he did every day, he saw the accident: "I saw it all, every last mind-numbing detail. And still do, every time I close my eyes" (p. 37-38). Since every time he closes his eyes, he sees all of his losses, especially the most recent bus accident, he no longer closes his eyes often, except when forced to from a state of drunkeness, which he calls a "frequently desired state" (p. 38). Since he was there when the bus had the accident, he was one of the first ones to help out at the scene and even helped out the rescuers. While witnesses of his help thought he was being brave, the truth was that activity kept him in a state of numbness, preventing him from facing the latest loss in his life.
In contrast to Billy, Mitchell is driven by anger, not the desire to feel numb. He says that witnessing negligence makes him angry, which makes him an excellent negligence lawyer. Hence, his anger drove him from New York City to the mountain town of Sam Dent in order to rally the victims to pursue a lawsuit, even though some of the victims didn't want to, like Billy, who saw that pursuing a lawsuit was dividing the peaceful town.
Hence, while Billy is driven to numb the feelings of his own personal losses, Mitchell is driven to action through anger, even though he hasn't suffered any personal loss. Billy's desire for numbness drives him to drink and want to keep the town peaceful, while Mitchell's anger stirs and divides the town.