You've gotten a lot of good advice here, so I'm not sure what I have to say that might contribute, but let me point out one thing I saw ... maybe it will be helpful.
This isnt their fault, it cant be. Logic states otherwise. The common element here is ME
As mentioned by others there are a few logical fallacies here, but one thing I didn't see mentioned is that it is common for people to have a 'type', even with friendship, and this can contribute to them continually ending up in unhealthy relationships.
For instance, when a woman constantly ends up with abusive men, it is often because she's choosing to date people who have similar qualities that she likes or is simply familiar with. It could be that she's attracted to 'manly men' or 'alpha males' which doesn't make them abusive outright but those are traits common to abusive men. Then there is also the familiarity aspect. She knows how to talk to and read that kind of person, and other people seem baffling or weird. Many people who are used to having unhealthy relationships who start having healthy ones often struggle because even normal every day interactions are so different and feel wrong.
If that is how it is for NTs, who get social queues and adjust to change in social situations much easier than people on the spectrum, it is an even bigger issue for us. We are even more likely to pick friendships because they have qualities we've seen or dealt with in other people so we know what to do and how to read them.
Unfortunately, just because they have positive qualities we like doesn't mean those don't go hand in hand with qualities we don't like. For instance, the same aspects of sugar that makes it taste good are also the parts that make it bad for us. Traits that are positive in some ways can be bad in others.
So, maybe you need to try out relationships that are different from the usual. Perhaps try relationships with NT's, people in the real world, etc. Just pick some aspect of how you pick new friends and look for someone without that trait. Yes, the relationship will be harder at first and will feel wrong, but if what is familiar to you constantly ends in something you don't like ... then maybe unfamiliar will lead to a better outcome even if it is scary to go into the unknown.
I can easily see your problems potentially relating to your friends being neurodivergent and/or online friends.
People who are neurodivergent typically struggle with relationships and anxiety in general, so are more likely to reach a point where they can't handle relationships for a while, finding them stressful and conflict laden. My girlfriend dropped the majority of her friends a few months ago simply because she couldn't handle the constant need to compromise and diplomacy that goes into them. She didn't dislike her friends, they hadn't done anything wrong, its just that relationships take even more work than normal if your neurodivergent and she couldn't handle it anymore.
In general, online relationships are often more distant with the sense that the other person isn't quite "real", which is one of the things that make them so much easier for people with social issues. You worry less about what the other person is thinking and feeling. If they get mad at you or judge you it hurts less than if it was in the real world. The distance makes it safer.
Unfortunately, that same distance also makes it easier to not see others as real people, almost like they are video game characters. Maybe not quite like that, but when you're alone interacting with people through your computer, where you can't see or experience how your behavior impacts them emotionally, it gets a lot easier to not worry so much about hurting them or worry about their feelings ... good or bad.
Like you, I often only have relationships with neurodivergent people and mostly online, and I have only had 4 people who have remained active in my life for longer than a few months, maybe a few years. For a long time, I honestly didn't think I'd EVER find people who weren't family that I meshed with well enough that they'd stay around ... but that eventually changed.
One of them is family, one of them is real world, one is entirely online, and one is sometimes online but sometimes I see her, she just lives 4 hours away so its rare. All four are neurodivergent.
Amusingly enough, they have very similar traits ... their personalities are almost carbon copies of each other ... and they are all pretty different from the people who didn't stay around. Which reinforces the idea that its about finding the right selection of traits for you.
So hang in there ... I know relationships are hard ... even more so for us ... and I don't know of a magic way to find the right people ... but if they were out there for me, they are probably out there for you too. You just have to keep digging through the coal to find the diamonds.