Legal guardianship. 16 years old. Please help me..?

I am 16 years old and currently live with my Father, step mother, step sister, half sister, and half brother. I moved out of my Mothers house 2 years ago this coming Summer due to her being unstable(alcoholism). When I moved in with my Father I continued cutting myself and my father would not take it seriously. I asked him for a psychologist at his house because I couldn't continue seeing the one at my mothers house(the distance was too far) and he never got me that help. I got bad grades the first school year and he grounded me the entire year which only made me rebel even more to him. Over that summer he began cheating on his wife(wife: woman he knocked up and left my mother for when I was not even a year old) and he put me in the middle of it as his messenger. But the thing is I can no longer live here. I am depressed, punished for minor things, I dont feel welcome or wanted, I have to buy all of my clothing myself(bras and underwear included), a majority of my possessions are touched or stolen and returned ruined or soiled, and I just need to get out of here so I can focus on my school work and not be in such a bad environment. The most important part is that my Father is a drug abuser (marijuana). My boyfriends mother wants to file for guardianship of me and plans to go get the paperwork to do so Monday morning. If we go to court and fight my father for guardianship will he be proven unstable and will guardianship be given to her? I live in Michigan by the way. Also, I am a vegetarian and my food accommodations are rarely met, I usually fend for myself, or my boyfriends mother buys me food to take to my fathers house. Someone please help.