How do you purge yourself of internalized ableism?

I've been reading Unmasking Autism (which I've seen reccommended here a few times) recently and am starting to become convinced that I'm Autistic. So much of what I'm reading there resonates with me, like the bottom-up vs top-down processing of stimuli, the desire not to be perceived, and especially the urge to mask so I'm not ostracized or targeted by society. However, despite realizing that there's nothing wrong about having the traits Autistic people have and masking being actively harmful to my psyche, I still can't shake the belief that all of this makes me unworthy of tolerating -- let alone accomodating -- in society.

To be clear, like most of my deeply rooted brainworms, I only weaponize this against myself and consider other neurodivergent people good and valid. Regardless, I can't help but see myself as a useless eater subhuman who should be Aktion T4ed if I can't twist myself into what I perceive society expects from me. Besides being horrible and wrong, this obviously has disastrous effects on my mental health. I've tried to fit myself into a socially acceptable box for so long that I don't even know who the hell I am under the mask.

One part of the book that especially devestated me was the exercise towards the beginning where I have to write down 5 parts of my life where I felt fully alive. No matter how much I wrack my brain, nothing comes to mind. I feel like I have no idea what I truly value and that, no matter of what I say or do, I'm always faking.

Besides the devastating effect this has on my mental health, it also gets in the way of me being an actual communist. I've put off organizing for so long in large part due to the fact that I'm convinced I'll be outed as a fake the second I try getting involved. To paraphrase Che, the drive of a true revolutionary is love for others, and I'm so trapped inside of myself that I can't have real and fulfilling relationships or truly, deeply, genuinely care about other people. How am I supposed to know and care about other people when I can't even know and care about myself?

I'm tired of seeing myself as an ontologically evil subhuman, but no amount of rationality and compassion has been enough so far to shake this fundamentally incorrect and harmful belief. I'm so tired.