I was never a prodigy. But I was a smart kid. I've learned to read only at the age of three, and my memory, or any other skills were not exceptional. I've read a lot and it gave me an edge over my classmates. I think I didn't really study at school but stayed at the top of the class until high school thanks to the knowledge I've picked up in early years.
I know what you went through from other jealous people. Dislike for smart ones seems to be universal in kids.
For high school I moved to another class, where everyone was gifted. Suddenly I understood that my erudition is not enough and my poor work ethics will not help me. I struggled to the end of the school, college and university, but my academic achievements were less then perfect. I have some regret over it, but not too much, because at the same time I've greatly improved my social skill. And that is much more valuable for my current life.
A few years back I started to practice the skills I was lacking or forgotten. I started reading again, after not doing it for several years. I started practicing languages again. Learned memory techniques. I'm still struggling with math, but it never was my strength.
The observation that might be useful for you is that mental skills are never lost. You may be a little rusty when you restart, but they come out of hiding real fast once you start practicing. And if you enjoyed it in the past, it's like meeting a long lost but dear friend - amazing feeling.
You write that your strengths were reading and memory and music. Start doing it. Read good books - the classics and make a slight effort to recall what you've read. Do it at a regular intervals after finishing. Start playing piano if you can. Try pieces that you enjoyed. You might not become the world leading pianist just like that, but you will help the sleeping talents to awaken.
You've already done the most important part - awakened yourself from the toxic thought patterns that were forced on you by the people around.
As for school, one of the goals of school education is to teach people to cope with difficult tasks that you have to go through with persistence. Sometimes, you have to sit down and do it in non-gifted way. This may be boring, but that's the rules of the game. Don't let it intimidate you. It is not making your talents unnecessary, they are just better applied in more liberal settings.
You know some of these topics may be truly difficult to do right and you need to practice to be able to get them right, memory and understanding might not be enough. This is hard for smart people to accept, but it is true.
Hope this helps, palimpsest. By the way you have a very interesting nickname.