Oh this should be fun.
Dear 16 year old me,
Effing grow a pair. You won't stop the bullying until you stand up for yourself. With that said, get your ass in gear and work harder on your homework. It's bad enough you're failing your World War 2 class, but if you don't step it up, the only way you're graduating at this point is if they use your overall grade and not your finals. Put the knitting down, put down the notebook you have by your desk, and of all things alive put the damned Game Boy advance down. That Pokemon game will last until you're 21 years old, and by then, you will have a new console.
And when you are done, still move home. That my dear is the only way you will be doing what you love today, any other choice will send your rear to an abusive relationship that you don't need to be in. And with THAT said, do not date your best friends brother unless all you want is heart ache.
Another thing...clip your nails...your arms are not a scratch board. Go back to the doctor and get re-evaluated for everything. You're not as depressed as you believe you are, and you are not mental.
Tread carefully around mom, now she's mental. You are going to fight with her, after all, if it wasn't for the man you married when you were 19, you wouldn't be able to stand up to her, she has to know that she can't ruin your life. Also, be prepared to have a massive fight when you're 22, you're mother will cheat on your step-father and she will try to not only hurt you, but everyone around you to make your life, and theirs, miserable.
Oh, and one more thing dear~ Buy a pair of crutches o~o you are going to need those. Trust me. Those ankles and your right knee will not be the same after your 20.
Your 24 year old self~