I would take her aside privately, before reporting her.
Tell her 1) what you observed exactly and when. You are concerned for the safety of the other pt's, and staff.
2) Tell you that find it difficult to work with her because of her anger. Try to have specific examples and quotes. People tend not to believe these kinds of things about themselves.
3) Tell her if she continues to put other pt's at risk with her lack of isolation technique, or by not following policies, you will have to take it to your supervisor.
I personally think it's always better to speak to the person as one adult to another before going to mngmnt, it is usually better received from a peer. If she is not willing to listen, or is extremely defensive, or threatens you, go to your supervisor.
As far as being nice to her, it's always great to try to have a good rapport with people, but on occassional when you run into a plain old crab, I no longer try to "win them over", I am there to work, not worry about if people like me or not, and I will not kiss someone's a$$ who is just miserable. Maybe there is something going on in her life, we can all empathize with that, but if she is nasty to you, how does she treat the pt's? No matter what is going on in her life, she should be professional enough to limit her reactions, meaning, maybe she can not not have any conversation at all, fine, better than being rude. Communication is a necessary part of her job, and no one should be allowed to be rude.