I enjoy psychologically torturing people, is that normal?

I once wrote a letter to a horrible woman I worked with basically telling her that everyone hates her because she is a total bitch and treats everyone like shit. I actually felt a bit bad but it had to be done. She was very bothered and wanted to know who has done it but I didn't write anything that wasn't true. I don't know if it made her rethink her ways but at least I tried. By the way this woman made me cry multiple times and called people names on a daily basis.