If there's a chance that something can be done and something positive can come out of all this upset, then you should take it. It affected you then and now it's still affecting your ability to do work, be more confident and have more self-esteem- all are very important. You wont get kicked out as you're a good student with great grades- it sounds as if there is no doubt that you will pass your degree really well from the results of your other work that you've been doing, and your sheer strength of courage and motivation to keep going, even when times are tough. Things like what this woman has done shouldn't have happened and are really unfair, I've been in similar situations so I really do empathsise. Please do something about it. If you do something about it then you will know that you have done all that you can with this issue, start to feel better and hoepfully work better too, you may also give others strength to stand up for themselves and be taken notice of if unfair practice is occurring again with her or elsewhere. What uni and subject are you reading for btw?