Dementia Support Group
Dementia is the progressive decline in cognitive function due to damage or disease in the brain beyond what might be expected from normal aging. Particularly affected areas may be memory, attention, language and problem solving, although particularly in the later stages of the condition, affected persons may be disoriented in time, place and person (not knowing who they...

My mother often talks to herself. She'll hold out a whole conversation with herself about how much she hates my grandmother, right in front of her, like she has no idea that any of us can hear her carrying on like that. I know she also has visual hallucinations, but so far, it's only been stuff like... she sees the color yellow on items that are not yellow in the least bit. (She apparently put half of her wardrobe in a garbage bag because everything was yellow and could "never be clean.")
She only gets violent when she is provoked by her obsessive compulsiveness. She got very upset at my grandmother for using a regular spoon to dip ice cream the other day. Like, so upset that she took the spoon, walked outside, and hid it under a seat. She's never threatened anyone just yet, but I know she's more than capable of at least hurting someone's feelings right now.
In the state of PA, however, if someone is clearly a danger to themselves or others and is displaying signs requiring an immediate psychiatric evaluation by a doctor, emergency services can force the person to go to the emergency department for just that reason. I am an emergency medical technician, and I have taken countless patients to the hospital for psychiatric evaluation, for the better. If your father is reluctant to seek medical guidance, there ARE people here to help you, I promise. If your state protocol does not support what we call a 302, then there is always the Department of Aging.
Allison has a good idea but depending on where you live it can be difficult. A psychiatric 72 hr lockdown in a hospital is a great thing since the doctors have time to see the whole person, however the police, EMT an doctor have to agree that he needs it. If your dad is a good ole boy and the locals like him there is little chance they will force him to go. You also have to consider that they won't be keeping him so you will have to deal with him when he comes home even angrier than before. They may give him meds but will he take them?
How about going to his pastor? If he is still such a religious man maybe the pastor can help. You could go to him first asking for counseling for yourself. In time he would have a clear picture of your dad and should offer help.
If you decide to walk away do it with your head held high. Many people have had to make this decision. I would jut do it in a way that will make a clean break. Maybe get a cell phone that you can give only to him so you can choose when you want to communicate with him.
He's religious but felt that the churches didn't know as much as he, so he left ages ago. He's a minister in his own right. This is part of his delusions of grandeur. He also claims to be able to see into the future, read minds, and stop death.
The arrest is important for two reasons. One it gives the officer the right to bring her to a hospital. And second it makes the police department responsible for the hospital charges if there is no insurance. This could work for you or against you of course if they have a limited budget. What I like is that the "blame" can be transferred to the police.
There is no reasoning with most people. They want their freedom even when they know it is not in their best interest. Very few people are willing to give up control.
Only you can make the decision. From what you describe I think you need to put some distance between you and dad. i'd suggest getting a cell phone so he has a way to contact you but you also can control when you talk to him. I'd also try not to make it a bad thing. Find a reason why you need to be somewhere else. Maybe find some things that he will let you help him with so you can keep an eye on him from a distance.
Eventually something will happen. We all battle that fear of the future. Balancing their independence with safety. Sometimes we have to let them "fall" before it triggers the next step.