What do you think I need to do?

My mom and I argue every single day, which usually ends with me in tears. She calls me names such as slut, worthless, stupid, and more. Last year I did a suicide atttempt because of all this. My parents did nothing to help me even though they knew about it. Now, those suicidal thoughts are coming back. I know living here is not healthy. I just turned 16 and live in Mississippi. Is there a law that stops me from leaving my house? She is starting to treat my brother the same way as me (yelling at him and making him cry too) I told him when I move out to never let her treat him the same way and I would try to get custody of him. What do you think I can do to get out of this situation? I have nothing left.