In my 30s, church became my only source of friends and acquaintances. However even then, I only made two “true” friends I still meet up with outside of church. Three, if I count my wife who I consider my best friend :)
The rest seemed like friends while we attended the same church, but quickly vanished as soon as we left (the particular church, not the faith). Maybe more of those relationships could have been nurtured to last if given more effort, but as both my wife and I are introverts, it wasn’t easy.
I’m in my early 40s now. We still attend church, but we find the whole social aspect of it draining. We attend worship…then go home.