M.P.
my nemesis at work used to do everything possible to make me want to do mean things. The list was so long. Even after promotion to AUDITOR of everyone's work going to the floor, I thought I had some clout and ask for her to be moved away from my area. After coming back from Christmas break I found she had been made my cube partner. She finally asked to be moved when I faked being interested in EVERYTHING that she did, and chimed in to EVERYTHING she was doing. She eventually quit or should say she quit before she got fired, but it wasn't my doing, she and another lady got into it and she slammed that woman's hand in a door. YEAH!
Guess my point is, kinda. Leave it alone, if she is worthless as a worker it will be found out at some point. She may just be a better friend than co-worker.