Why mom so strict-worst case (REALLY)....?

wow. Im sorry! My situation was quite the same, I ran away with my boyfriend at 18, still with him now. Life sucks especially that kind of situation, all you can really do is tell a teacher that your step father is abusing you, or shut up and deal with it until you are able to move out. In this situation the parents have the ball and there's not much you can do.