Backstabbing staff

I have an employee that's leaving(I'm her superv) and she's already done an exit interview with the higher ups and apparently bad mouthed me. This is a delusional, problem employee- never met expectations, always poised with excuses... My boss knows her history as I have a file of write ups.
Problem is, my boss won't tell me what she said until after she leaves and I am ticked that she even bothered to tell me and not be forthcoming Now. So I have to put up wth the two faced B for another week. The entire office can't wait until she goes- not just me!
I tend to react and want to defend things just so it's clear what I'm responsible for or not. I have no problem being held accountable but for the higher ups to give a pita staffer a forum is undermining. Whatever. I am
Just venting.

I would feel the same as you. Fortunately, a week usual passes fairly quickly and she will be gone. Vent away.
Gayle