@Patrick802, lack of communication is my pet peeve and in business, especially our business of someone coming into our home, communication is peace of mind.
I fine it disconcerting when a guest does not communicate or answer any of my messages. It is very rude not to respond to a message and it takes only a moment for someone to respond to a message, even if it's a, "Got it, thank you."
I find most people who do not communicate are the instant bookers. Of course, they are also usually the ones who have several verifications and reviews, which helps, but I still don't like when someone does not take even a moment to acknowledge receipt of a message.
In this case, you might want to call her to check in with her and make sure she is still coming and verify the time. Tell her you have something going on and need to verify the time.