Others have great suggestions, but I’ll take a different approach with some practical advice that came to mind. These are just ideas, so feel free to workshop it or to dismiss it entirely.
Advocating for yourself in person can be really difficult. I’m quite a people pleaser, so I know how it feels to go into a situation with an idea of what you want to say and leave feeling disappointed that you didn’t stick up for yourself. You seem like you’re fighting an uphill battle with your age and the doctors’ previous responses.
I think you’re a pretty decent writer. I really felt for you as I read this post, and I can tell that you’ve struggled. The doctor that you want treating you will be someone who is moved in the same way and will care about you enough to get to the bottom of this.
I think you should change the main text of this post into an email template that you can address to different doctors. Maybe add a blurb about only wanting to be their patient if they’re willing to treat the things you say with trust and validity. Then, start sending it to doctors/neurologists around you. If those don’t get a response, then expand your range. You might have to travel or make some life changes to get the treatment you need.
Hopefully you’ll get some responses. From those responses, you could gauge how you feel about each doctor. For the ones that seem like they genuinely want to help, you can visit their office and get an appointment. Don’t treat going to an appointment as a commitment. You’re shopping around to get the best treatment for yourself.
Hopefully yet again, you’ll find a doctor that feels like they’ve got your back and is willing to take you on as a patient because they really care about you, not because you’re just another “customer” of the healthcare business.
Ask for help even though it might be scary. You’ve already done that here with this post, and I of course don’t know whether you’ve done it elsewhere. If you haven’t done it on more personal forms of social media like Facebook or Instagram, then try there. People are usually more motivated to help if it’s someone they know that is suffering. Even if you haven’t talked to most of the people on there in many years, people will still read it, and some of those people might know something that could help you.
Depending on how comfortable you feel on those platforms, you can reach out in a vulnerable way like this post or you can keep it more practical by just asking for doctor suggestions. Also, if you want to hide the post from certain people (maybe your parents), you can do that pretty easily on Facebook with the “post audience” option.
I hate that you’ve gone through all this suffering, and it should NOT be this difficult to find a good doctor. The system here in the US is really horrible to navigate and inhumane. I’m sure doing all of this would be exhausting, but if it gets you what you need, then I think it’s worth it.