There are extremes within any population, but on average, at least among young adults, those who feel lonely actually spend no more time alone than do those who feel more connected. They are no more or less physically attractive than average, and they do not differ, on average, from the non-lonely in terms of height, weight, age, education, or intelligence. Most important, when we look at the broad continuum (rather than just the extremes) of people who feel lonely, we find that they have the capacity to be just as socially adept as anyone else. Feeling lonely does not mean that we have deficient social skills.
John T. Cacioppo, Loneliness: Human Nature and the Need for Social Connection
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