work place hell

There is this incredibly annoying woman at work. And she HATES me. This is not an exaggeration either. She loathes me. And the thing is, I could care less whether or not she likes or dislikes me. I would, in fact, prefer that she totally leave me alone. I don't desire to talk with her or relate to her and frankly find her to be a lazy piece of poo who is a burden on our team rather than an asset. And the rest of the team also believe this to be true but because of a long past involving this woman and human resources and management, she appears to be virtually unfirable. But lately she has taken to finding subtle ways in which to harass me. She follows me on break almost every day. She eavesdrops on my conversations with other co-workers and then repeats them to other people. She also has said some incredibly stupid and vile things about me to a co-worker/friend who has since warned me to not say anything around her. But today I reached the end of my rope. If she were a good worker, I could overlook her evilness but she's not even that. So I reported her to my manager and said that I found her behavior harassing. And inappropriate. And uncalled for. And was basically told that it was my words against hers and what could they do? So now I don't know what to do. I know that she is hoping that I will freak out on her so she can remain the victim and I will get in trouble. So I won't play into her game. But at the same time, how am I to stand idly by while somebody harasses me, even on a subtle shallow level? It's not okay. I'm not sure what to do and clearly nothing is going to be done despite the fact that many people list her as one of the reasons they quit when they leave. It's BULLSHIT!