Kids and marriage also make it practically impossible to not meet other people.
If someone did a study on loneliness vs fertility rates, it'd probably be a near perfect correlation.
The modern era of Tinder, normalised deviancy, and so on is really setting people up for a very uncomfortable later life. And I say 'later' but it's really the overwhelming majority of your life, especially if you discount your earlier years where we're all just basically retarded.