Advice for stepmother!?

Ok...So I have a stepmom and she and I do not get along hardly ever. I am such a nice guy. Im 16 yrs old, am in the top ten of my cl, never talk back to my parents or anything, and NEVER ASK her to do anything for me except just recently to come get me from work after school and she kinda volunteered doing that after giving me crap about it. But anyways. She is always trying to find something to get me in trouble about! I mean always. If its not one thing then its another. However, her kids not me but her real biological kids she never puts on punishment and when she does once every 3 months they still get away with it and never have to be punished. THEY TAKE OVER her, However, I do not mess with her or anything and me and her never get along and when she is in a good mood I fake liking her because I know the next day she'll go right back to doing stupid crap and being angry at the world. I rlly need help! What should I do. I have the option of moving to my Moms but I only have 2 yrs left until college and right now I have a very nice job and am doing good in school. What should I do? I don't want to confront my parents about it cuz everytime we do have a "talk" we all cry for a lil bit say were sorry and then about two days later me and her are back to normal hating each other. I cant take this crap anyone with her always insulting me and treating me like crap and not EVER saying anything back. Im about to explode!!! I have sooooo much crap built up inside of me and her adding to the pile everyday doesnt help. Im starting to even fail school cuz all I think about is my stepmom and what she yelled about me this morning before school on the way to school. WHat to do? Help PLZZZZ!!!! and fast.