Nobody drives them far away in a truck, never to be dealt with again. They simmer and bubble and finally make themselves noticed again. That's when somebody gets sick or hurt. People who keep painful feelings inside don't start out with a wish to become dangerous to themselves and others. No, they simply fail to realize that even the most painful feelings can be transformed.
Broken hopes are a lot like pieces of glass.
They can be used to hurt someone, or they can be transformed into something useful. The energy that it takes to be angry can be used instead to work for change in the community or to achieve a personal goal. On an everyday level, there are plenty of examples, too. A boy I'll call Steve tried out for the football team at his school. He did his best, but he didn't make the team.