If she knows you are going on a guys weekend, she'll think you are being a jerk for doing it while she's getting over her surgery. IMO, she needs to believe she's pushed you too far. She should know no details. And tell her not to contact you unless it's an emergency.
It is important that you get some leverage in this R, b/c she has continued to play the same old song & dance much too long. It's time to put a screeching halt to it (if you haven't waited too long). That is why you don't tell her any more than you are leaving for a few days, maybe longer. Her questions should be answered with you saying, "IDK".
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!