do you like your manager?

about 2 months ago, I got an invite to go to a lunch thing at my job, but at a different branch.
It said it was a welcome lunch, so I assumed it was for associates who started at the same time I did, again, across multiple branches of the same company.

No one said anything to me about it, and I wasn't interested so I trashed the invite that magically appeared on my desk, again, like 2+ months ago.

Well that lunch is tomorrow. The manager sends an email to everyone saying we should have recieved information and to let her know if we are not going.

I said I wasn't. (gluten intolerant)

Manager responded with " Why are you not attending, you are expected to be here".

So you wait til the last minute to get a 'head count' on attendance of an event that I wasn't even told about...?the name on the card was someone I didn't even know...

Anyway, I told her that I have food intolerances and I don't know what's on the menu so I'll be at my desk working...

If she writes me up, I'll make sure I save the email. She is beyond ridiculous, I have more instances that validate me.