Yeah it's typically because we start to feel the heat as we age. It's seem so obvious to me that
the last thing the world needs is another single man.
You're bound to become, in the eyes of others 1) a weirdo than will act as, or rather will manage to, get tolerated as a third wheel. AT BEST. Because what comes next is...
2) a loser that will be openly shat upon 3) more potential competition for foids, making you the target of incessant normie one-upmanship 4) a dangerous single male creep, potential rapist/pedo that hasn't been vetted by his goddess to truly enter society. Those are strictly in relation to other people. I'd say that this actually starts at puberty but is more or less pronounced depending on the environment, but it fully kicks in as you become older as an adult.
The other layer of this is the broken interiority, as you said :
Loneliness and sexual starvation are kinda self explanatory.
But the lack of identity is rather new and totally soyciety's fault.
I kinda touched on this subject in another thread recently but i dont know if i made myself clear enough. A man does not really have a strong identity nowadays cause identity is, no matter what anyone says, strongly gendered. Guys nowadays can't naturally cultivate it in their interiority, because it's universally discouraged and looked down on to perceive anything as intrinsically male, in the name of egality and inclusivity... while at the same time, women still have a demand, although in a vague and often self-interested way, for gender roles

and society at large still judge you through those roles. So yeah good point to mention it cause it definitely has it's place next to the other two factors. It's confusing and a source of mental anguish, and i'd like to point out that there's nothing virtuous behind it, cause leftists and others like to euphemize it by using fancy sentences like it's an "evolving change of paradigm

" or some shit when in reality it's just permanent male abuse, an ongoing mutilation of the male polarity and it will never fucking change. They'd retort that then, a man should "just strive to be a good human being

" but as i said, when you interact with people, especially the other sex, or even just walk down the street, no one sees you as just a "human being"

this is some stupid leftist ideologue utopia.
Yeah as i already said it a few times on this forum, guys nowadays actually hide behind women's skirts because of this toxic zeitgeist, no matter how openly awful they can be, they will ignore all the redflags, everything, to be with one. But this is not a volcel manifesto, i mean, this rather acts on it's own and it's not really our fault, as
@Limitcel said it's more like an oversocialized reflex.