I want to first let you know that I have no background in psychology or therapy and what I am sharing with you are totally just my personal reactions and are not meant in any way to be seen as any sort of professional advice (because I am clearly not a mental health professional).

So, when I read your story, I was at first very saddened that you had such a difficult childhood experience. But I was also really amazed (and impressed) with the overall tone of your story. Even though you describe some pretty horrific things that a child should never have to experience, you don't seem to be fostering anger or resentment toward your parents. Your insights seem to recognize that your parents were "incapable" of raising a young child effectively. I think this is a great realization on your part, because it sounds as if both of your parents were likely mentally ill (again, just my reaction, and definitely not a professional opinion).
Also, I think your assessment of yourself and where you have come from and where you are currently seems really introspective to me. You mention the possibility of AS, but I have to say, I have encountered MANY people with AS and I have never seen any hint of that level of self-analysis and/or reflection in any way, shape or form in ANY of the AS people I've known over the past 20+ years. That's not to say you don't exhibit some other characteristics that might be associated with AS, but could also be related to another possible diagnosis? (the thing that came to my mind was was 'dissociative', but I don't have enough experience or knowledge about that, so maybe I am completely off base on that one). Anyway, if you do exhibit some dissociative tendencies, given your childhood, you would certainly have every right to do so, in my opinion, and you may have resorted to that in order to cope with your traumatic childhood.
Are you currently seeing a mental health professional (psychiatrist or therapist) on a regular basis? I noticed you listed your current diagnoses and your meds, but I am unfamiliar with the meds you are taking. I have ADHD and am Dyslexic and have struggled with anxiety (situationally, in the past, but it can sneak back in at times). I know I'd not be able to live any type of a normal life without my medication and I also know that sometimes I need med changes or med levels adjusted in order to live a productive life. Also, if I had not had a therapist help me work through some of my issues in college, I would not have learned how to address several of the problems I had growing up and I wouldn't have developed many of the coping strategies that I use to help me work through my "stuff" on a regular basis, even to this day. Also, if I didn't have God in my life, I'd be an absolute wreck. That's all I'll say about that, unless you would like more info. about that and you could Private Message me.
Overall, you seem like you are in a place where you are really ready to receive help. So I would say take your time to find a good mental health professional to help you through the process of healing and moving forward with your life.
You are 21 and you have been through a great deal. But you are still young and you seem eager to change and grow and I believe that will really help you in your journey.
Welcome to PC and I hope you will explore many of the forums here but also use them to seek professional help. Because this thing called "life" is not meant to be done alone and sometimes we need help from professionals to move forward and there's nothing wrong with that