> "...loneliness wasn’t necessarily from being alone. In fact, it was often a feeling of alienation while in the presence of other people."

So true. With the political polarization so common now, you can become isolated and then alienated quite easily.

I'd add that being a man, especially if married, as you age your social circle radically declines. Getting divorced radically improved that for me. And I'm not even talking about the opposite sex - I have more guy friends now that 10, 20 years ago. There's a space that NO wife or GF can ever fill...