I'm realizing that a significant proportion of white middle class Americans have little to no concept of hospitality, and thus their isolation is no surprise. My parents were like this and I chalked it up to them being weird, but it's apparent that this is actually the norm for many people.
Such people may have parties, guests even for the long term, etc etc, but there's something missing and hospitality is the best way I can name it. It seems like a learned skill that's missing.