The people who are telling you that she does it because you are allowing it are correct. We will get as much crap as we are willing to take.
Because of the deep feelings I read in your post, I disagree with the "just ignore her" approach. That's not working for you.
One problem is that you allowed it to get this far. It's time for some one on one confrontration. I realize it's quite hard and may not go well, but you need to be heard by this person directly. Going to the manager or charge nurse isn't going to help you. But it might help after the fact to let the manager know "I've had a talk with Adrienne about her bullying and this is how it went.........".
There's a good book called "Crucial Confrontations" http://www.amazon.com/exec/obidos/tg...46524?v=glance
that can help with some of the skills.
Talk to her, tell her how she makes you feel, ask her to stop and then each and every time, without exceptions because this gives her permission to continue
call her on it. "Perhaps you didn't mean to belittle me, but you just did, why? We agreed during our conversation yesterday you were not going to do this. Plesae don't do that again". Keeping a written journal might help.
When I needed to confront a CNA where I worked I kept a journal and mapped out what I needed to say, how I was going to say it, and even though I thought "it won't do any good", I still did it. Guess what? It worked. The issue was resolved and she knows what I expect.