imo, for everyone, especially once we get older, it seems that the social circle gets smaller.
I have my gf, i have my best friend (diff state) since we were 13, and we have a couple friends down the street that are neighbors.
All through out my life i have gone through cycles of being able to be around people a little bit, then i will isolate myself. and repeat the
pattern.
My gf and i have been and living together for 5 years now. She is the only human who i've not felt the urge to isolate myself from.
I have shutdown and had her right next to me, yet we have never been apart.
Normally i would be fine going through life being a hermit living with animals.
There have been times in the past though, that isolation has made me stir crazy so i went to a gamestop briefly interacted with the cashier clerk and had i guess an "interaction fix". (i don't know what to call it)
I am imagine that NTs that are very social actually need to continue their own socialness in order to thrive.
Also, the longer i isolate myself the more damaging it is for me when forced to interact with humans in public. I have found it has made it harder on myself, and worse for me to interact with others after i have not been near or talk to any humans in a very long time.
I get more anxiety and stress from social situations after i have isolated, it is so much worse.
Yet it is a pattern than i'm used to doing. Since i've met my gf, i feel my isolation includes her and sometimes i worry i am isolating her. Yet she seems content without any other humans aside from me. Right now she's playing Skyrim (yes, i swear she's NT) and she helps me a lot especially to avoid a lot of situations where i could be socially uncomfortable.