Loneliness is correlated with basically almost every negative health outcome you can imagine. John Cachioppo was leading a researcher on loneliness. He found that lonely people don't spend any less time with others than none will do. If you feel good about your relationship, but you have time alone, that's solitude and it's a positive.
Eric Barker teaches our curator Daniel Pink how to make friends, disarm marital conflicts, and spot liars.