Maybe I make it myself too easy with that, but often when I read about loneliness and how to deal with it, it comes from people who have friends and a relationship. So it seems they are just missing that tiny little bit til perfection.
Maybe my scale is a different one, but for me loneliness is when you don’t have all these social “basics“ to start with. It’s not about struggling to deepen existing connections, it’s having none at all.