I'm fairly certain, now, that it was her, it got put back on my desk "mysteriously", out of thin air. Hmm...and she never said a word about it.
It's not just this event, it's other events that make me believe this could be a possiblity. I'm not overly nice to her, I say good morning and just try to be generally polite. I don't carry on conversations, however, with ANYONE at work--that's just me. I'm there to do my job and that's it.
She's worked here way longer than me, I just got here and she's been here for years. My boss did mention to me that she felt I didn't like her for some reason, and did she say something to upset me? I do think my boss is fair though, because it was mentioned that she can be moody, and I just have to take her as she comes.
I think you're right in that I have to give her few opportunities to sabotage me, and everytime I step away for an extended break I will lock my work up in my desk!