Etienne,
I can relate to your predicament. I, too, was raped my sophomore year and am about to finish up my senior year at the same university. It really is a tough road, and I want to tell you how great it is that you have gotten so far.
You seem to have a strong support system at your school. That's a great thing. The problem is this: is being in a place where you are so uncomfortable hindering your recovery from this? Does it make it harder to confront the memories, feelings, and aftereffects? Do you still see the guy? The other thing to remember is that no matter where you go, you will still have the memory. You can't run from it (believe me, I tried) and you can't make it go away by leaving the scene.
I lived in the apartment where I was raped for almost a year after it happened because I was stuck in a 12 month lease. I was pretty miserable. When I was able to move, it didn't solve the basic problems, but it did help because the situation wasn't on my mind every time I walked in the room. That helped me realize that it was in the past, I had survived it, and I would get better. It could be the same with you.
If you are truly uncomfortable at your campus, I don't know that it is worth it to stay there and hurt for another year. I ended up putting off graduation by a semester because I dropped some classes so I could deal with the stress. It was a really good decision at the time. If you are miserable, then you have to make the space for yourself to get better. You might take the semester off and decide on the basis of how you feel. If being without the support of your sisters is really hard for you, harder than it has been to be at your school, then you can re-enroll. If you feel better not being there, then transfer. That would allow you to keep your options open.
Also, I would really suggest that you try some counseling. It can really be helpful, especially in facing things that linger on about the rape.
One other reccommendation. I have been on an email support list for about a year now and it has been a real help to be able to talk to people who have been through things and see their positive outlooks and hear good advice. The list I am on is based off the website
http://survive.org.uk. It has played a really huge role in letting me recover.
Hope I haven't blathered on too long, and that I've helped a little.
Many hugs from a fellow survivor,
Elisa