Im a 16 yr old girl who is hated by her mother,she dont want me to be happy and she neglects me all the time.?

she is threatening to call the cops on me just because im dating someone who makes me happy.he just turned 18 today and she is going crazy about it.we've been together for almost 10 months.anyways,my mom is trying to make me move in an apartment with her.its a 2 bedroom and there will be 9 poeopke living there including the newborn.where will i sleep? i havent had a bed in ages i sleep on the floor.sometimes my mom doesnt even feed me.right now im staying a few nights and i actually get to and have a bed to sleep on and im school zone at my dads,but the problem is my dad has NO custody of me.i need helpfinding a way to change this and live with my dad.im scared.im sooo stressed about this and a 26 yr old girl shouldnt be stressing.my heart is broken.and im the good child,but she hates me the most I DONT UNDERSTAND! how do i get out of her hands and into my dads? i need anyones help especially a cop or law person who knows this stuff.come on i cant sleep in a bathtub because my mom doesnt care about me. :( please help!