I have no friends or partner, I’ve been very lonely.
When I go out to try to meet people, no one ever comes up to me and starts talking to me. But if I want to meet someone I have to do exactly that. But like, why should I have to be the one to initiate 100% of the time? Shouldn’t it be 50/50? (And I’m not really talking about societal expectations of the man initiating with the woman, I’d rather have a boyfriend anyway.)
I have such a hard time initiating conversations with people, to the point where I mostly just stress out and sit there alone. If someone initiated with me things might go better. But they just don’t.
The only reasonable explanation I can think of is that literally no one has any interest in me.
I think you're fundamentally misunderstanding how a NT person experiences social interaction. It is almost entirely unconscious for them. They are running on literal monkey social software, no offense to NT comrades of course. They make connections, form relationships, and interact with very little conscious thought. The problem with using this monkey social software is that it has the morals of a monkey. I.E. it identifies the other, that being you and me, and unconsciously removes you from the potential friend pool.
If you could ask them "Why didn't you talk with me?" they probably wouldn't be able to give you an answer. The best is an ad hoc "bad vibe" which just means you're ND in 95% of cases. But unless they are intimately conscious of how their brains process social information they literally have no idea why they won't talk to you. Because of this, you have to be the one to break through to them. It sucks, think of it as a person of color having to work 2x as hard to get the same job as a white person.
The "good" news is that once you break through to the friend stage your behavior no longer gives off "bad vibes" and you just become the ND friend. Use their own unconscious bias against them to make friends. If you act as if you're friends with someone they'll feel the social pressure and ad hoc think of you as a friend.
Here's a guide I made a bit ago on this topic. It's what's worked for me so far but take it with a grain of salt.
i'm so tired