Hi guys;

It has been a while since I have to be put up with my co-worker's bad manners and bossy attitude.
I am an incredibly shy and nervous person who hates confrontation and just the though of it makes me stressed to the point I physically shake all day and get strong headaches.
I am not assertive and I get confused on why I can't really confront her. In my mind I feel like telling her that I do not appreciate to be spoken to in that manner, and next time she adresses me to do it it respect, but as soon as I think of saying anything I just start to shake and end up just doing what I am told.
I am afraid to say it and to be embaressed but then I am embaressed because I did not say anything and other peopto probably think I am stupid.
I am an adult, I have a family and hate been spoken to like that makes me feel really used. I get emotionally tired and drained but I cannot make myself say anything.
Would should I do, how would you act?
I am sure my attitude is not normal, my head tells me one thing but my body does not respond appropriately. It is incredibly frustrating.