Sudden decline. How quickly can this happen?

Msblcb, the problem might be a case of Urinary Tract Infection {UTI]. Such an infection in an older person can cause all type of problems. Your Mom can have a test done at her primary doctor's office or at an Urgent Care. This can be treated.

When I visited my mother this week, she didn’t know my name.

It was the first time that had happened, and even though I knew it would come, it jarred me.

Dementia is SHATTERING. 😩

If you think that she still remembers you, at least most of the time, it might help you both if you make a habit of saying your name, calling her Mom, even referring to yourself as daughter, each time you first see her. That will help keep her memory fresh, and probably be less difficult for you.

Yes, most likely she had been declining overtime. Dementia affects the memory, thinking and behavior. Symptoms eventually grow severe enough to interfere with short-term and long-term memory. Support groups and other services are available, you are not alone. https://www.alz.org/help-support/community/support-groups - Alzheimer’s Association virtual support groups + online community/message boa