@Lisa1539 This guest will NOT become any better...
Call CS and have AIRBNB cancel her 2nd trip as soon as possible. Reason:
You feel uncomfortable (everything else will result in a punishment against you)
and refer to her own health issues, messages and complains
Notify the guest and again refer to her own complains.
Re-List your place and get a HAPPY-Camper.
I got this right? You agreed to a discount after they complained the last time?
So if yes, and if it was THIS BAD for them, why they even want to come back.
Do them a favour and let them find something else. 😉