The (non-)answer is that it depends on your husband's nature and the effect dementia has on him. I've known people who will aggressively deny they have dementia right up to the end.
I suppose I've been lucky in that my wife realised she was "losing her marbles" (her words not mine) and accepted it in a positive manner as "I've got Alzheimer's, what can I still do?".
We've tried to jointly make positive steps to make her feel more secure in her increasingly confusing world. Although she is aware of the overall progress of her dementia we never discuss it in medical terms, just what she will be doing.
This makes it sound as if I've found the perfect solution - NO WAY - things go wrong and we get as tired, angry and frustrated as anyone else, These are the good bits of a very rocky path. Hopefully there is something you can pick out to add to the extensive good advice you've received already.
"Positive" actions were:
Tell everyone, it's not something to be ashamed of. (Ignoring some of the "expert" replies is a bit more difficult).
Sort out LPAs so my wife didn't have to worry because she couldn't understand her money.
Sign up for brain donation and Join Dementia Research. My wife always wanted to donate her organs so this seemed a positive thing to do. As a result we've met some interesting researchers and visited some hospitals and universities.
Join the local Dementia Cafe, Singing for the Brain etc. These provide an environment where a person's condition doesn't matter. They enable us to meet people with a wide range of conditions so my wife feels that what is happening to her is normal (there must be a better word). They are also good places for getting tips and local advice. I particularly recommend these for helping a person gain an awareness of their condition.
Sort out a care home. This isn't possible for everyone but my wife selected her own care home which deals with daycare through to nursing care. From daycare she knows many of the residents so staying there for respite care wasn't an issue for her.
If only life were that simple.