My bipolar sister is making me feel like I'm the crazy one...

My older sister was diagnosed with bipolar when she was still in elementary school, probably around the age of 10 or 11. She was hospitalized for a period of time (I was really young at this time), for probably 3 or 4 months. I remember going back and forth from my hometown to the city where the hospital was with one parent, while the other stayed there with her.
My childhood was everything anyone with a mentally ill sibling could come up with; I was harassed, assaulted, locked in my room by her, verbally abused and neglected to name just a few. My parents would never back me up when we got into a fight, and it always left me feeling like I was unwanted. After her hospitalization things got a little better, but there were fights every night because she would never want to take her medication. The smallest things would "set her off" and whenever something happened (which was often), I would be promptly told-off by my parents.
There are some happy memories, like Christmas, but they are so far and few between that they don't really have any effect on how I feel.
But jumping forward a ways(I'm in university now), I still hate her more than ever. Last year my parents sent me to see a counselor/psychiatrist because I needed to "get help" for saying "hateful" things about my sister to my friends (I was always told when I was little to never say anything about my sister's mental illness to my friends, but I did anyway because they were my only support network), and for the first time in my life I found out that the way I thought and felt was completely normal. This woman validated all of things that I had been feeling my whole life, and even encouraged me to press assault charges (after finding out I had been talking about her to my friends she attacked me in my room while my mother stood by and watched). However, had I chosen to do so my parents probably would have kicked me out of the house.
I'm on the verge of moving out (I have a job lined up in a different state with plans to attend school there), and everything she does irritates me. She's a complete pig who makes a mess anywhere she goes, then tells my mother that I did it (keep in mind that she's 26). She has bad personal hygiene and goes around reeking of BO and other odors associated with an adult woman..... All of my life she has been entitled to my stuff (clothing, video game consoles, underwear, you name it), and used them freely regardless of whether or not I gave my consent (and my parents certainly didn't stop her). Most recently, in anticipation of my move, I purchased a fairly (I think ) nice car. I have been saving for years and splurged on it. To put this into perspective though, I have to provide a little background; I have had free use of my parent's vehicles up until this point, one of which is "nicer" and has power locks and windows, and the other which is just as nice, but has manual locks and windows that my sister and I mainly shared and was "our car". When I got this new car, she suddenly didn't want to use the manual-lock one anymore and after failing to convince my parents that she should be able to use my car, she is now only using the power-lock one. If she can't take the "nicer" car she demands to be driven places. They see nothing wrong with this behavior.
My life is full of crap like this, and I can't wait to get out of here and never have to see or speak to her again. I'm just so tired of feeling like I'm the crazy one and I want to get out and finally live a normal life.