Lots of good advice so far and as usual by TBNers. :thumbsup:
First and foremost, as others have said, don't take it personally. But what does that really mean? A better phrase might be to not let your dads actions and words get to you emotionally. This is much easier said than done. At first. But eventually, it does get easier and you can deal with the outbursts.
I have to deal with people with mental illness professionally and in the family. With one situation, our hardest realization was that a family member was mentally ill and how we would behave/react to situations needed to change. What we were doing was just fine for a normal situation but what we were doing and saying was NOT going to work with someone who is mentally ill. This required a complete change of behavior and actions on our part. It took us a while to realize we had to change our approach. As part of the change, we had to NOT take things personally even when hurtful and untrue things were said directly to us. You just have to let that go by. Water off a duck's back type of thing.
Get as much information about dementia as you can. Our county has a large elderly population and as a result there are services and people to talk to about dementia and elderly issues. Check to see if you county has something similar. You county might also have a social services department that can be of help. Heck, it would not surprise me if the Extension Office had information. Talk to YOUR doctor and get their recommendations.
After you make your first pass at getting educated on dementia and what local resources are available, try to talk to the NP and see if she will help persuade your dad to go to a specialist. Suggest to the NP that the NP cannot see all of your dads behaviors because she is not around him often enough. Explain that your dads behaviors are dangerous and very likely to cause the loss of employees and maybe the business. Hopefully, the NP will then help persuade your dad to get to a specialist. Worst case, maybe the NP will just help out to pass the buck and cover their fanny.
I would also try to explain to the employees that something is wrong with your dad and you are working to solve the problem. Ask them to ignore the bad stuff your dad is saying. Again, this is easier said than done but communication is key. If the employees know you see the problem and are working to solve it, they will be appreciative. If the don't see you recognizing there is a problem and/or trying to do something, they might just quit and move on.
Unfortunately, taking care of elderly relatives is part of life and it is not easy at all. For some reason the wifey and I were discussing this last night. Her dad died sorta suddenly last year. His health had declined, then got really bad but we figured he was still doing ok when he suddenly died. Thankfully, he died rather painlessly and without suffering too much. He and the family were lucky in that regard.
Here is my most important piece of advice. TAKE CARE OF YOURSELF. Part of the services available locally is help for the SERVICE PROVIDER which is YOU. The person taking care of the person with dementia has a great deal of mental and physical stress. As part of your talking to doctors and other service providers, part of what you should be asking is how to take care of YOU. If YOU are not healthy, you cannot help your dad. This is like being on an airplane where the cabin pressure drops and the oxygen masks are deployed. You have to put on the mask first before helping the kids. Take care of YOU so you can take care of your dad.
Later,
Dan