Vin,
Been there...done that.
I also work in this area and see it every day. Call the Alzheimer's Association or go to
http://www.alz.org now. These people can be a great help for your dad and a great support group for the family.
It is very hard to acknowledge the problem and to make the decisions necessary for the apporpriate care/environment. I always fear for the spouse, because they are very hessitant to disclose abuse they are receiving from the incapacitated person.
My thoughts go out to you and your family. Please contact the Alzheimer's Association at your earliest convenience, you will be happy you did.