Julie, I do understand. Many think the memory issues are the first symptoms of dementia but in many cases it is the behavior and judgement that changes first. They do become paranoid, self absorbed, and seem to lose their social filters. Nothing seems to suit them and they will accuse you of the most amazing things. We went through all of this with Mom.
I also understand that we think we know but when it is our loved ones it's different. I worked in long term care with dementia and thought I was clued in. Then my Dad was diagnosed with vascular dementia. He was so easy going and cognitively aware for many years. Mom on the other hand, with her Alzheimer's, has been a hand full from the beginning. I missed her diagnosis for too long. We want it to be something else.
As for Dad, you just have to keep talking to him, explaining to him, and trying to convince him. It could be something else that is treatable. Only a physical examination with blood work and test along with an evaluation of her medications will give you those answers. Instead of saying Mom needed to be diagnosed with Alzheimer's I went under the pretenses of a good physical. Use a birthday or other event that you can use to convince her it is time for the doctor to take a look at her. Even a sore shoulder or knee will do
Then I ask the doctor to do a MMSE (Mini Mental Status Exam) that will give you an indication of her cognitive abilities. If there is reason then you can let the doctor refer and be the bad guy.
If Dad does refuse and the situation become unsafe for her you can do one of two things. You can call adult social services and ask them to do an evaluation. If you indicate that the living situation is hazardous to either of your parents then they will investigate and take the necessary action. Or, if your Mom becomes combative or out of control you can call EMS and have her transported to the ER. They can asses and make recommendations. If she is bad enough they can do an involuntary commitment for evaluation despite your Dad's wishes. These are extremes and I do hope you can convince Dad to have her evaluated... even if it is to prove you all wrong
Not having the ability to make the decisions is difficult but you have to keep trying... for both of their sake. And just remember that you are their best advocate!!
PS... demented behavior can be manic. When the confusion fogs the brain there are behaviors that mimic other behavioral problems. Mom was depressed, manic, hysterical, anxious, paranoid.... She is not on anti psychotics for her behavioral issues and chemically content
This despite the fact that she had absolutely no psychiatric issues until after she started showing symptoms of Alzheimer's .