Colleagues always do personal things at work, and they always ask me to help her with her work. It's disgusting.

Just watch what she does in private first, if she plays with her mobile phone to send text messages or cut her nails. . The next time she asks you to help her with her work, you can say that you also send text messages or cut your nails, so don't be a sinner. She is embarrassed to say that what you do has nothing to do with work, because she also does this writing at work.