How can I move away from my dad's house? (difficult situation)?

My parents have been divorced since I was five. Until I was 11, I lived at my mother's house happily, and I never really got along with my dad. In many cases, there was some abusive situations with him that were scarring, but I learned a lot about inner strength. But at my Mom's, we always had to go visit my Grandmother and aunt all the time so they could babysit us, for lack of a better word and they were often emotionally abusive of everyone around them. When my mom started to get very depressed, after my brother moved out and a series of other events, I started to feel suffocated by the affection that she layed on me out of fear of losing me. I saw it as a huge problem for her and got very emotionally crazy over it so I decided to move over to my Dad's to give the situation room for change. For a while I kind of liked it, but I still never got along with my dad, or my stepmom whom he cheated on my mom with and married just after the divorce. She is scary controlling and they fake smiles and laughs to fool people into thinking they are okay. But when you live with them you find a much darker side. My mom got much better after the move and she saw my point and we get along great again, but now I am stuck at my dad's and I don't want to be. It is starting to get very stressful and manipulative. I have told them several times in the past couple of years that I want to go back to her, but they sidestep me and tell me it isn't what I want and negotiate, and the situations get stickier. I don't want to take it to court because I don't want my mom having to spend tons of money that she doesn't really have. I'm 16 and I should be able to make a choice, but I'm not being allowed without making it difficult. Please help?