Why should people learn to be "unsociable" when they reach middle age?

When people reach middle age, they don't have to get along with people they don't like. When I was young, I would spend some time with them for various reasons, but in middle age, I don't have to force myself. Since you don't like it, there is no need to endure it. Happiness is the most important thing. When people reach middle age, should they study? Not gregarious? , enjoy? Not gregarious? The loneliness that brings you. Gradually, you will understand that true feelings and happiness are the most important things. So-called? Not gregarious? I just don't want to please and cater to others anymore. Follow your heart all your life, Do not forget your initiative mind.