How can i legally live with my aunt I live in indiana and she lives in michigan.?

My mom moved to indiana with her and my 4 younger brothers. Im the oldest and im 14. After a long (6 HOUR) arguement she decided to let me finish my 3 months of middle school there in MI. She spanks my brothers and threatens to choke/kill us everyonce in a while. We now live in a small 2 bedroom trailor in indiana with her, us 5 boys, 2 dogs and my grandpa. We only have 1 bed for grandpa and 1 blow up mattress 4 us. Theres alot more but i wanna get emancipated or something so i can live with my aunt in michigan until im 18. HELP ME PLEASE!!!!!