How do I get out of this family situation?

Hello-I'm a 17 yr old girl living with my Dad, stepmom, and 3 siblings in TX. I moved in with this family exactly a yr from christmas from Red Riv, NM after living with Mom and brother. I came here because I wasn't doing good in school and my Mom and I were not getting along. Now, I'm doing good in school (B- at lowest) and my mom and I have an awesome relationship. Anyway, after living here I feel that my family (mostly stepmom) are way too involved with my personal life. Recently, she and my younger stepsister read my diary. I had lied about a few things and had a few bad things in there :/ and i felt horrible about it. So I got punished for the lying and the things I said in there. But people are telling me it wasn't my fault and i shouldn't have been punished. Idk. I feel they are way too involved- that they know everything about what I'm doing. They check my checking account, grades, cl attendance, read my messages, stalk my facebook page, and they rummage through my things. They question me constantly and they get freaked out over the smallest things: i locked my keys in my car the other day and there were phonecalls made around to all of the family to ask if there was anything I wasn't telling them. They think I'm a lying conspirer. Really this all pisses me off- they stalk my life and I never get to live like a normal teenager. I never drink, do drugs, smoke, have , or anything. I don't even go out of the house!!!!!!! What do these people want from me? I know they love me and care for me but they stalk my life and "care too much" I guess. Ya'll would understand if you seen the way we live. They are so paranoid that I'm a bad, sneaky, lying kid. This christmas we've all decided that I'm moving back to NM and that might fix things. but what do i do for the time being???? It's driving me frickin' insane. help