Have she seen her doctor since this began? You should let her doctor know what you’ve described here and schedule a visit. There could be several reasons for her behavior and an evaluation is needed
Just an alternative possibility: The plan my DH and I have talked about, if we want the easy way out, is for me to stop taking my BP pills and for DH to take them instead (though his BP is fine). I’m told that it’s not necessarily such an easy way out, but perhaps it’s the way your mother is thinking herself.
Maybe she is tired of doing what she is told. My mom said she got tired of me, my husband and my dad telling her what to do and when. We shut up and we were all much happier. She was happy.
Sounds like she is having trouble navigating normal life skills right now. Maybe she has an UTI? Maybe something else that is throwing her off kilter?
Is anyone helping her with her pills or with food prep?
Good luck!