Looking for advice on multiple diagnoses

In my experience when a professional evaluates me and I fit every single criteria for something and they don't want to give me the diagnosis I find it's almost always because there's a stigma about how "rare" the disorder is, combined with the fact that I was assigned female at birth, am fat, and have anxiety. It's like they see these things together and say there's no possible way anything else could possibly be going on it all must stem from being emotional and on my period, being anxious, or being obese. Take for instance me fitting every single criteria for dissociative identity disorder and almost every single criteria for autism, every test saying they're definitely all fit, the professionals still refuse to entertain the idea that something 'sssooo raaaare' could POSSIBLY affect someone like /me/. So if I were in that situation again, i would start looking at the interesting things that make doctors and psychologists suddenly unable to diagnose literally anything. Are you someone who is typically considered to be a marginalized voice? This will significantly decrease your chances of being taken seriously, especially if you have multiple marginalized factors; they DO stack! Were you assigned female at birth, or intersex? Are you any race other than white? Are you plus size, even to the point of only being a large if you're assigned female at birth? Do they ask you invasive questions about your menstrual cycle when you present these new potential diagnosis discussions? Have you ever talked to them about anxiety to any degree, especially if you have a diagnosis of general anxiety disorder? Are you working/labor/lower class/poor/impoverished/houseless? If you answered yes to any of those questions, you may be a victim of medical neglect due to rampant stigma, and a general knowledge of 'everything' that limits and reduces the quality of what help you'd be getting, rather than a specialized knowledge of a particular thing. Usually the only thing that gets me looked at and taken seriously to any degree is when I compile a literal three-ring binder with pages upon pages upon pages of sourced research, even more pages about how I fit each characteristic described within that research, the differential diagnosis of what else it could be with reasons as to why I think it's not that, and include things that other people in my family and friend circles have said about me, and comorbid diagnosis, and family history of similar diagnosis. In other words sometimes in these situations you have to become your own doctor and just hand them the dang binder with everything all laid out and spelled out in front of them. It's the only way they'll give it the time of day, because this way they can scan it to see if they can find a reason it isn't that, then when they can't they'll suggest taking a deeper look at it. And when you're talking about your symptoms you don't need to talk about your symptoms as though it's that day that time etc, you need to talk about your symptoms as though they are the worst of the worst that they get for you, because without divulging that information the general Dr/psych will simply say that they still don't think you have it. Or you can spend lots of money and save lots of time and get a second opinion from someone who actually specializes in that field and isn't just a GP or general therapist or regular psychologist. That does a lot of good for helping get the diagnosis.

I have EUPD (emotionally unstable perosnality disorder) and if your gp doesn't think you have what you think you have you have 2 choices- A- trust your gp or B- ask a second GP