This reminds me of one of your posts not long ago, about depression serving a purpose. (Was that you? Or @agmoore? Maybe both in a conversation) We get depressed so that our body rests, in short. Here, we experience existential loneliness in order to pry open the portal that allows us to see within. perhaps existential loneliness is above all what echoes from that part of ourselves that we never dared to explore.
More generally, all symptoms are a body's response to an illness, and contain messages about which way to look to find a solution and get back to a state of balance and health. If we ignore these symptoms and persist in the negative thought, the body will step up its attempts to notify the person and come up with something even worse.
Natan needs a hobby, bad. Without one or more hobbies to help find his self worth, any relationship he is in will sooner or later show him as too needy. Twenty years of marriage later, his wife will be kicking him out of the house just to get a break from him.
Poor guy. It doesn't have to be so hard! Enjoy time alone, I do! And I have a zillion hobbies. I experience existential loneliness when I have not made the time to engage in my music, poetry, cooking, gardening and simple walks in the woods.
During my emotionally lonely patches I was quite married with three children. I was never ever alone, but never fulfilled either.