My mother does not believe she has dementia. She only forgets the “petty things.” She resents my involvement in her care. Everyone but her realizes she needs 24/7 care and can’t live alone (she’s also an amputee) yet she tells people that she drives, cooks, cleans, etc and none of that is true. When I correct her she gets angry and looks at me as if I am the one who has “lost it.” I try agreeing with her but that makes her angry. She tells me the caregivers don’t know what she does when I know they do. I think in her mind she is in the past back when she was independent.
Acknowledge what she's said, and then ask leading questions to bring her closer to the present - if you happen to have time, that is. Neutrality and focusing on the task in hand is fine, if you haven't.
I like the "petty things" - very familiar! My mother only couldn't remember the name of the Prime Minister because "he's such a nonentity."
I read your profile. I did it all too with my mom (Parkinson’s disease). I empathize with you. You need help. This is too much for one person to handle.
Many here do have experience. Hang around and people will give you advice.
Best wishes to you and your mom.