Friendship Struggles & Constant Social Rejection

(28F) I went my whole life undiagnosed until this past July, and friendship has been something I've struggled with about as long. I don't know how common it is to struggle with this & even just making friends in general.

I was constantly told in my life that there was something wrong with me & I believed it for years. I am repeatedly socially outcasted in every irl situation I try to be a part of; including jobs, group projects back in school & even within my own family. Similar patterns started happening when I tried to be more social online. People really misunderstand me; so much so that I've been painted as this massive, narcissistic bitch when that's never been the case. I always gave 120% of kindness, care & joy to others. Sometimes I feel that I'm speaking another language with the looks I'm given by others.

I've masked my entire life; always molding into forms that would make other people happy & help lessen the abuse. When I've unmasked in the past, that's when I've gotten massive amounts of hate & anger from others. The same people who told me to be myself were the same people telling me that I was "too much" when I tried to be what I thought was myself (I still struggle with identity). I was labeled things like "trauma dumper" when trauma was all I knew how to speak about. I had triggers & boundaries disrespected, causing meltdowns that gave the other person some kind of "justification" in their mind to be rude to me.

I've lost so many people that I considered "safe" friends that I no longer trust any human & have developed a fear of people. Friendships always follow the same pattern:

• We become friends instantly. We get to know each other & spend hours just being around one another; we share our pasts as well. Sometimes they offer support when I am struggling & vice versa.
• there is a sudden shift in the other person's personality; they become more negative, angry, they pull away from talking to me more. Almost as if a mask came off; sometimes brought on by events in their life at that time.
• there is a fight where the person is screaming at me after I bring up issues from their behavior towards me that make me uncomfortable (because I thought friends were supposed to communicate). I am blamed for everything and told that I have all of these issues that make no sense to me & don't really align with how I am as a person.
• the person either blocks me, ghosts me altogether or starts attacking me either online, publicly or to their other friends. And I am left confused, abandoned & taking days/weeks to mentally & physically recover from losing another person. The time length to recover takes longer the more often this happens.

I can't comprehend why this keeps happening. I always wanted to be friends with everybody, even though that's not possible. And I'm left questioning my worth as a human being & being led to believe that I shouldn't exist. It also makes it more difficult to understand who is a friend and who isn't. I never wanted to be alone, but I feel so hated by society that I'm not even allowed to exist anywhere without being outcasted, having slurs thrown at me, being given dirty looks or being kicked out of spaces that I thought were safe. I don't think life is supposed to be like this.

So I wonder if this is a common thing for autistic people to experience. Constant social isolation for being literally wired different. How do you keep friends? How do you not find bad friends? How does friendship work when you're autistic? How do you be a good friend to others? How do you know if people are being your real friend? How do you handle social rejection & isolation?