I hate my stepmother what can i do?

Get into counseling right away. You're dealing with alot considering your real mum just died. You have self worth issues and need professional help. It's easier to talk with a stranger about your problems usually. Have your dad go to a few meetings with you and explain that HE is your parent and you want him to stop letting his wife take control. You have 3 more years to go, try to make the best of it.