I've been there. When he's in a certain mood, my uBPDh also has a great deal of trouble making choices. I, too, would get panicky and desperate, trying to make a choice that wouldn't upset him more. And, yes, the situation would just get worse.
For pwBPD, emotions tend to be out-sized. Also, feelings=facts. If they feels something, then they will twist the facts to match. So, if she felt pressured about the show, in her mind, she believes you ALWAYS mention it. Is she lying? No. She probably genuinely believes that you always push it.
The key for me -- and what will probably help you -- was to work on myself and my reactions. You can't control her. But you can control yourself. It sounds to me like you're so tied to and dependent on her emotional state that your own thoughts and emotions are in a whirlwind. Again, I've been there. If you can disentangle yourself from her, it may very well lessen the number and intensity of these episodes. Even if it doesn't, YOU will be stronger and better able to function.
How do you do this? It's not easy. You need to start recognizing what's yours and what's hers. Her feelings are hers. Your feelings are yours. When I started reminding myself of that and focusing on staying calm, it really started to improve things. If I choose something he's unhappy with, he may sulk, but eventually he gets over it and -- up-side -- I enjoy the food or show or whatever it is that I want.
You know she has trouble choosing. Pushing and pleading with her isn't working, is it? What could you do instead? (And keep in mind if you change the pattern, she may react negatively at first. Long-term, though, it can lead to positive change.)
The two of you are getting caught in this pattern and circular arguments. She's probably not going to break that pattern so it's up to you.
To help, you might want to read this article about setting boundaries:
https://bpdfamily.com/content/setting-boundariesI'm sure others wiser and more experienced than I am can pitch in and help!