My mom doesn't do anything.?

Shes been unemployed for 10 years, she's 40. She free loads off my stepdad who works two jobs in the police department. He is never home. We have 4 kids living here. I'm 16 and my bro is 18 and my sisters are 4 and 7. Well she doesn't do anything besides lay in bed. Be on the computer or boss people around. She has a weird problem about having control over people and she takes advantage of it. She never lets me outside the house. She forces me to play sports in highschool, she dropped out of college but still frowns upon the fact that my brother dropped out of community college but only for a full time job where he is happy at now. She lost her ability to raise kids. She spoils one of my sisters and barely gives the other attention. She doesn't discipline them. They constantly fight. I feel like more of a a parent than she does. She never cooks food. And she refuses to do laundry, dishes or trash. She will walk right by simple chord like that, even though it's just common sense to just take care of your own house. She acts like she does everything and will get so offended if you just ask her to do something. Shes stubborn and will NEVER admit she's wrong, she's arrogant and has NEVER said sorry. So what do I do? I love her but she is difficult to live with, being lazy and arrogant and acts like she does everything when she does NOTHING