I been through the same thing with my Dad. I was tired of him pushing me around and shit. For about two months, I ignored him. I didn't say "Hi" or anything whenever I saw him. I would either eat dinner later, after everyone's done and doing their own shit or I would buy my own food. Whenever he tried talking to me, it would end up in a argument & I would just leave the house and go for a walk. You're not overreacting. Parents need to learn to give their kids, especially the older teens, some space. Siblings should know better than to pick on their younger ones, at least to the point where they have to end their communication. I feel you. My second oldest brother picked on me a lot. He beat me up once & I threatened to call the cops. He sorta stopped there. But we didn't talk for the longest time ever. I removed him from my contacts & every social networking shit I had. Anyways, good luck to you.