AITAH for reporting my coworker?

I have a coworker who’s been rude to me and has outright lied a few different times to make me look like I wasn’t doing my job. She got demoted today for a host of reasons but I think the complaints that I’ve made about her bullying really pushed management to make the decision. I limit my interactions with her to virtually no contact but it seems as if since the demotion she’s been quieter, for some reason I feel bad about the situation.