first, thank you for the compliment of asking for my feedback. i wasn't always assertive; it took time and experience to gain self confidence in my skills and assessments.
while i no longer let myself be taken advantage of, i also don't get upset easily. even a pt who is alert and oriented can have a bad moment or bad day and may end up yelling at me for no particular reason. usually i remove myself from the situation (as long as the pt is safe) and return a bit later to attempt to engage in conversation to figure out what may be the cause of the pts anger. as i said before, we're on the front lines and readily available for a pt to vent their frustration. after all, no one wants to yell at the almighty physician! (though this is slowly changing). often i've found that it's the pts attempt to control their situation....they may feel that there's nothing else they can control in this environment. we see them at their most fragile and vulnerable moments, while at the same time examining every inch of their body. also, for some pts, yelling and arguing is a part of their normal living environment (unfortunately) and they haven't learned other skills to cope. again, most verbal tirades don't phase me anymore. of course, if it were a continuing barrage despite my efforts at remedying the situation, i would insist that the pt/family member talk with social services or the nurse manager.
when a pt is demented, delirious, etc, it is not unusual for them to act out physically. if i know a pt has a history of hitting, kicking, etc i will bring in another staff member if at all possible when caring for them. keeping a calm, soothing voice may be helpful, as may a no-nonsense yet cheerful demeanor. don't let them feel your trepidation or anxiety. if you are confident and professional, this helps. there are times when there is just nothing you can do to prevent physical abuse except medication and/or restraints. it's never the first choice, but a viable option.
pts who are demented who may pat my bottom or some such thing are usually easily redirected. i just don't make a big deal about it. if a pt is alert and does the same thing, he/she will get a very direct, no-nonsense "that is not acceptable." usually that is enough. if not, i will absolutely have another staff member with me if i must enter the room and i report the problem to my nurse manager. i've never had it go beyond that.
i find staff to staff hostilities to be the most problematic. we tend to be passive-aggressive and would rather complain about someone than confront them. i think you acted appropriately at the time in the situation you described. you even attempted to talk with her in private....kudos to you. as you said, you didn't know about the chain of command at the time and so were left without recourse.
i'm sorry that this is so long....i just started typing and my fingers didn't want to stop!