Some people cannot be alone while others stress out around too many people. I think many of us who prefer solitude find other people disappointing. That's how it is for me. Also, people who can't be alone are usually very uncomfortable with themselves for whatever reason. They need constant reinforcement from others that they are okay.

My favorite quote about happiness comes from the Dali Lama. A follower of the Dali Lama once asked him, "I want happiness, how can I get it?" to which the Dali Lama replied, "Take away the I, for that is ego. Then take away the want, for that is desire. What you have left is happiness."