I know this is old, but I just wanted to update:

I thought of a great way to solve the issues she was raising, sent an email telling her what I was going to do, then implemented it. It was good because while it did fix the issues she was having, it didn't 'give in' iykwim. (I thought that would just lead to another thing to complain about as it had in the past) and I even got brave and finished the email similar to what Grinity suggested!

The outcome? She isn't speaking to me. smile Which is kind of weird, but I'm basically ignoring it and it really is an improvement. And most importantly, I feel okay about myself and how I acted and I don't feel cowered and bullied. And while I don't know what she has said to others, either they are good pretending or they haven't cared. (Since they don't seem to have noticed she isn't talking to me, I'm not sure what they think actually.) It's a very interesting place to be...