Anonymous wrote:OP: It is very hard to get out of the box of expectations that you are in. They will never promote you because they cannot replace you. No one else would do 2 jobs for one salary. Time to have the umm humm, yeah you are so great! lunch and then move on. No employer gives a bad review to an employee who is leaving -- too much chance of a lawsuit. The 18th century is over now.
I found that at my previous job -- I would always say yes to weekend work, took the crap shifts, etc., then discovered there was no promotion, not even a raise. After I had a kid and my wife asked I stop working so much and change my shift, I found things didn't really change and people were still expecting the old me to be there.
So -- after 10 years with that company, I left.
Just be non-committal at the lunch. Certainly don't let it be known you're looking outside the company.
Exception: If you think this boss has the pull to reduce your workload, then ask her for help in reducing the workload. You may find you don't mind staying if that's the case.
But, as 22:27 says, she probably has no real help to offer. Just deal with it, and keep on working and looking for a new job.