Greetings,
I use the 7-stage model for dementia, but keep in mind it is sometimes easier to gauge stages in hindsight rather than while you are in the arena. Sounds a bit like Stage 4 or even 5, which for me as a caregiver was the most difficult transition. Perhaps because at this time our loved one has progressed beyond the simpler "I forgot your birthday" stages.

For reference, here is a very simplified explanation of the 7-Stage Model for Alzheimer’s and Dementia.
Stage 1: All is well. No dementia.
Stage 2: You notice something is “off” with your loved one, but no one else does. Very mild cognitive decline. You may notice, but doctors, loved ones, and friends do not.
Stage 3: You know something is wrong, and others sense something is “off.” Mild cognitive decline. Loved ones begin to notice, decreased performance at work.
Stage 4: Everyone notices. You enter panic mode and begin seeking help from doctors. This is your transition from spouse to caregiver. Early-stage dementia, moderate cognitive decline. Difficulty socializing, concentrating, forgets recent events, trouble with finances. Day/date/time difficulties. Caregiver(s) becoming more involved in managing tasks for the patient.
Stage 5: Your loved one can no longer manage alone. Mid-stage dementia. Needs assistance with all activities of daily living. No short-term memory. Confusion and forgetfulness. Urinary incontinence may begin. Caregivers seek hands-on help. This is when caregivers seem to discover this forum, many of them already desperate and exhausted.
Stage 6: Speech makes no sense, personality and memories are completely gone. Mid-to-late-stage dementia. Does not know anyone’s name. Communication difficulties, both in speaking and understanding the spoken word, inappropriate behavior, may be agitated, wandering, no longer recalls personal history, address, or phone number. Double incontinent. Must be supervised and managed 24/7. Caregiver(s) require help now.
Stage 7: Can no longer walk unassisted, nor eat or drink without assistance. May be bedridden. Late-stage dementia: Difficulty eating and swallowing, angry outbursts, loss of speech. Must be supervised and managed 24/7. This is the final stage before death.

I hope you find this helpful, and I am sorry you are on this awful journey with us.
Love Bill2001