Well, that is a trying past, it must be hard to draw confidence and inspiration from such an environment. Sometimes these events can ear mark your thoughts and behavior, you must remain future orientated and not past driven. Learn from mistakes others have made, recognize THEIR bad judgement and contribute your better choices to help yourself and others as best you can. I have observed that people who are focused, working toward something and remain genuinely interested in you are strong, good people. You can communicate, you are at no disadvantage. People see "difference" and don't understand it. Any negative expression is from insecurity, your difference reminds them that their difference could be exposed. so you have control over them. You should be humble that you can see through it and let it go. Because you are mute, you should focus on others details, what they say, wear, body language and build in your mind the perspective of how they are feeling. Take a genuine interest in people and remain focused on your work. you will become confident because you master a topic, interesting because you know the details about a topic, and valuable because you care about others and how they are going.
"maybe the internet will be a better place" This often isn't the case, but when real life's been crummy, it can be a great place to retreat.
There's nothing wrong with asking for compassion and you've got some from me as well as others here, I'm sure. My advice to you is to realize that high school will be far from the best part of your life, and you should focus your energy on doing well academically. Once you graduate, you'll have a much bigger world of opportunities. Being a mute will be an obstacle, but there is still way more than enough in life for you to be able to find something that makes you happy.
Best of luck. If you ever need to talk to someone, feel free to send me a message.