How can we deal with Dad always negative and angry?

Depression is always in the differential diagnosis of angry, negative behavior, especially if not terribly characteristic of the person before, or much worse than usual for them. Sometimes Rx for that will help a great deal.

My mother also has Alz/dementia and is angry. It is very difficult to bear at times. Some of her caregivers have told me that people often act the opposite of how they were before the Alz/dementia and this is true of my mother. The negativity and anger is caused by anxiety and stress. The anxiety and stress is being caused by the ongoing brain damage from the disease. Your father needs to be seen by either a neurologist or geriatric psychiatrist who can prescribe medication that should help him. The good news is that there are many medications that CAN help. For my mother, we put her on Risperdal and that calmed her down greatly. Unfortunately, after 6 months, she began to have a reaction to Risperdal and is now being taken off of it. I'm not sure what medication she will be given next, but there are other medications that CAN help. Psychiatric medications are a bit of a crap shoot. Some work for some people but not others. Some work, but only after 6 weeks. Some don't work at all and other medications must be tried. Sometimes the medication works, sort of, but the dosage must be adjusted to get to the right therapeutic level. So patience is required to find the right medication(s) in the right dosage.

In the meantime, you need to know that Independent living is not appropriate for an Alz/dementia patient - especially as they progress along the course of the disease. Your father will need Assisted Living for Memory Care and then finally a Memory Care Unit.

There is a free book on the internet that you should read. It is called "Understanding the Dementia Experience" by Jennifer Ghent-Fuller. Google that paper as it will greatly help you understand your father's situation and what is causing the anger and agitation.

There is also a book that may be of help to you called:
"Elder Rage...or take my Father, Please: How to Survive Caring for Aging Parents" by Jaqueline Marcell
This book can be ordered from Amazon.

Wishing you all the best.

Since you stated your dad has alzheimers there may not be anything that can be done to stop the negativism he is displaying. (I think I'd be angry too if I had that illness; and he simply may be trying to express his feelings. I doubt it has much if anything to do with you.)

Still I suspect if this were occurring to me, I would "feel" it. One way to help yourself may be to simply reframe all your dad says to you. Example: If he is expressing anger at you, just repeat what he says using your own words and adding that you understand those words were not meant for you. (This probably would do nothing to stop his venting; however, it can "implant" some additional information in your own head that his words have nothing to do with you.)

I read that your dad is in an independent living situation and he has Alzheimer's. It would help to know a little more about his situation so people can give specific comments. Your dad is negative and angry. Why? How does this affect him and you? Has he seen a Dr. who has placed him on meds for Alzheimer's? What do you do when he gets angry?

Give us a little something to go on.