Im just like you. Whenever I got stabbed always I kept quiet and kept it to myself. I used to think that my actions speak louder then words and people know me and that I'm not someone like that and I don't want to paint her badly so I don't say anything back. I also used to think that this is a childish phase people would outgrow.
But my career coach told me that I'm actually doing myself a disservice and I. Should just tell everyone what really happened and stand up for myself.
I started to realize wherever you go no matter how high you climb no matter how old you get this always seems to repeat. Now it's a colleague. In the future it might even be your boss.
People who say that your manager should manage her well are right. But it's too idealistic. In a perfect world yes. But in reality. How many managers are well trained enough to know how to handle this? Most of them are just trying to figure out being a supervisor day to day on top of their work duties. Some of them don't even care until you throw your resignation letter then they say "oh I didn't know it bothered you so much why didn't you talk to me?"
The people who ostracized you are easily swayed sheep. I know it's easy to be hurt by this. But focus on the big picture and focus on what's important. Are they important to you? If yes do something about it. It no. Then stand up for yourself and ignore the noise.
What matters is you gotta be strong and learn how to deal with it.
For your sanity. For your future. For your happiness.
Also if you think that you might be facing depression. Please get some help.
All the best.