Mom is slipping deeper into dementia with more memory lapses and confusion. Yet, she sometimes remembers a small detail from 60 years ago. She seems to be sleeping more and more. Getting up in the morning, eating a little and going back to bed. She falls asleep in her chair for long periods of time. Is this more sleeping farther signs of what I am dealing with?
You didn't say if she had a caregiver, but maybe someone to swing by daily & check meds, cook a meal or "clean house" for an hour?
If/when she is in the final stage, I highly recommend having hospice care come in to the house.
Memory loss varies from one type of dementia to another, but in general it is short term memory that suffers the worst. My husband might not remember what he did yesterday but he could tell detailed stories about his school bus driver from 75 years ago. Remember details from long ago while having lapses about more current events is just the nature of the disease.
I wouldn't worry too much unless she is missing meals, losing weight, or lack of activity is robbing her of any lucidity.
Have you checked with her doctor? Might want to make sure her health is good, she isn't anemic and she is getting enough nutrition as well. Maybe find someone who can visit her a couple times a week, make a daily phone call to her or invite her to senior center to keep her mentally stimulated and having something to look forward to during each day.