It seems at least possible that her intentions are good, and you don’t want to blow up your job, right? Have you told her directly that you like her and like your job, but the lunch-and-interrogation is not your idea of a break, and you do need a break? With a smile, do not feel like you are doing anything wrong. You are not doing anything wrong.
I am surprised nobody else is sitting these out ever, if every other person in your group looks forward to the lunches and they are part of what she considers the culture of the department, maybe it’s important to her. But I have never worked anywhere where it was a requirement like that.
Are you Hezbollah and did you buy a phone from Israel? Did you piss off the mob, or a government? Then maybe. Otherwise, unlikely. Phones have been known to catch fire, though.