For my parents and their siblings that meant the furthest apart they were until mid life, ignoring war service, was around 50 or so miles. Not by choice, but there were jobs, opportunities and housing locally. Not in each other's pockets like in a small village, but near enough to meet up regularly, visit when passing, take me over to my uncle or gran if they needed to go somewhere. There was some overlap between friends. There was always someone pretty locally.
For me and my siblings, friends and cousins, we are a far flung bunch, and it is the same for most of my friends. I have a relative 300 miles one way, one on another continent, another 200 miles the other way who I've almost completely lost touch with. Some friends have even more far flung friends and family. For the most part that seems to have come at a high cost. Not just when someone is taken ill, or at Christmas, but in day to day life, in our ways of parenting, in our closeness (or more accurately our lack of closeness) in day to day life. The lonely mum stuck miles away from relatives, the dad trying to keep it together alone. Maybe it even explains some of the addiction to social media.
Maybe I read far too much into it, having reached an age where mortality is far more apparent, and people I thought as young have died. My parents and their peers seemed to have had a level of contentment with their lot, even though many were in WW2 - sometimes at great cost, that me and my peers have utterly lost.
I have no answers. I wish I did.