Julie, with my mom who has vascular dementia and turns 91 Friday, her personality became magnified as she clung to her reality. The neighbors were against her, people were stealing from her, she saw people in the house when she was alone etc. She was always right and everyone else was wrong. It is very hard to contend with some phases of this disease. Sometimes you just have to keep a watchful eye on the situation and act when the situation is right. Like Deb said a doctors appointment or when she is having a meltdown. The only good and terrible thing about this is that they change as time goes along and somehow the situation becomes more manageable. Your father will definitely have to have help in the future. If you have to less than honest with your mother do it. Sometimes it is the only way. Keep posting and feel free to vent your feelings we are or have been in the same boat.