I have the feeling, you encountered a person that went to a reader, not so much for your reading but rather needed your admiration, respect and undivided attention as a "fellow esoteric/ spiritual/ gifted" contemporary.
Maybe her own social circle got tired of the kind of "lectures" you mentioned she gave you??!
I feel, more than anything she needed you to affirm, that she is a medium......
(I have a sinking feeling, that she is not at all, but rather "full of an over-inflated ego....)
In the maaaany years I am reading for others I met a few of these misguided individuals and it is at times a little tricky, to put them into their place.
(Luckily I personally have my Shamanic Medicine Guides that them come to the rescue and tell me all kinds of very personal things about an individual like this and when I use the cards in a "creative" way to point these things out, they very quickly realize, what true medium or Magic or reader Power really looks like and that they are actually quite far removed from it.
But I agree, these encounters are draining.
Now: First, put a feather onto your cap!
You deserve it for having made it through such an experience and for having shared your feelings about it with other readers and so made them aware, that these types are "out there"
Then; This person came to you for validation. You gave her that, so she might come back, because other looooong time readers like me would not let her "get away" with that.
Ifff she shows up again, tell her you will not read for her again because you saw through her game. -It however is entirely possible that a person, conducting herself like that, is not even aware, why he/she is going to a reader - or any other provider of alternative services, where for a time she is serviced with undivided attention.