Okay guys. Here's what I did. I offered to use the payment toward any non-Saturday event within the next 12 months - if not already booked. That's the best I can do and she said multiple times that she understands my position. I feel we are still on good terms. I just hate the whole situation. 2020 can kiss my ass.
Good for you on not caving in. Sounds like you handled it expertly. You're a stand up guy (well except for maybe your political views). All the best to you.