Separate two of you is the best idea to take care of the situation. Normally, one of you need go away.
I think you still need write down the stuff that happened between you and her for future reference. In the mean time, let your boss deal with her. You want to stay as far from her as possible.
When you discipline an subordinate you need make sure carefully document everything from time to location to reason and what type of disciplinary action taken from verbal to suspension. Make sure you have a good open door police and have female witness with you while you talk to her. Have her sign the paperwork after disciplinary paper. (check your management training material for similar procedures.)
Keep your mouth shut in the company. Bad news travel fast.
Good Luck!