I have a colleague who I have now worked with for over 12 years. She has always been quite difficult, very up and down and not sure if she likes me one day and not the next. She used to be a manager in my department, but low down, she wasn't anybody who was making decisions it was more just day to day running the department. When she was in this job I was obviously a lot younger, didn't have much confidence and she was okish with me. Lots of other people had issues with her but nothing was ever really done because she is actually good at her job.
A few years ago she changed roles. Still working in my department but actually for a different company. I see her everyday and our roles now mean we are working more closely. Her company offer a product and part of my role is to promote it basically.
A few years ago I was promoted and I have always felt that she thought I wasn't worthy of it. I know I am and I have just ignored her since really, always professional, but really her opinion doesn't matter because every other person is happy with my performance. She is definitely someone with a chip on her shoulder, extremely judgemental and just not a nice person really.
To my point, a few months back she was quite sneaky and tried to get me to do something which would basically be testing me at my job and she would see the results. I've done this task many many times and always done well so I wasn't bothered about doing the task but I was bothered about her being involved. I know whatever feedback I got she would hold on to it and have that over me. I spoke to my manager about my reservations and she agreed and cancelled the whole thing. Since then my colleague has been awful. She doesn't ever speak to me, that's fine, but whenever she walks past me will raise her eyebrows and storm past, look me up and down with a sneery look on her face. She has snatched things out of my hand, not saying thanks and just generally being so rude. She has tried to get some of my job tasks moved to different colleagues, which makes an impact on how much money I make, two separate people have told me this. I could go on and on about her behaviour really, it's not always just me, the whole time I have known she picks on people she doesn't think are good enough. My question is whether it is worth bringing up her behaviour with my manager? My manager knows exactly what she is like but doesn't ever do a thing. I think it is harder now because she doesn't even work for our company any more. The thing is, I know she will never ever change and I refuse to let her get to me but I want her to know her attitude is wrong and absolutely no one should think they can treat people the way she does and it just be accepted. I'm really unsure what to do and whether to rock the boat even more because it won't change anyway.