I’m so glad you wrote. The reason you aren’t getting anywhere in your arguments is that you aren’t arguing about the real problem. It looks to me like your mom is having a very difficult time letting you grow up, have your own opinions, and eventually leave home. She may have become too dependent on her role as your mom to envision a life without a child. It may be frightening to her to be on her own when you go to college.
Obviously, developing an eating disorder is not the answer to her criticism. It only hurts you and validates her opinion that you are the problem.
Please stop arguing with her about every little thing. Try to instead have a conversation about how things will change for each of you as you grow up. On your side: Talk about how important it is that you start practicing making your own decisions. Instead of arguing about how ADD effects you, figure out together how you can learn to manage your ADD so you can be successful at school. As for your mom: Ask her to think about the many things she will be able to do once she doesn’t have to organize every day around your needs.
If attempts at a mature conversation go nowhere, you need some outside help. Often adults will listen to other adults better than they listen to their kids. Do talk to your school guidance counselor about whether they can help your mom understand that there is not appropriate college nearby as well as what you need to do now to be successful. Consider seeing a family therapist to help the two of you separate in a way that lets you both feel good about it.
I wish you well.