Sheriff Willoughby killed himself and left 3 letters. One for Mildred who was not very happy about him. The other one for Dixon which really turned him to a decent person. Anger begets greater anger. Yeah, and very tiring actually. But I think when you were in anger, you wouldn't know it was also painful until you got a hint and starting to forgive and let go. And then you finally felt released. It's too tiring to be in anger as much longer as you want.