No worries Millwall,

there were several occasions in the early days when my fathers 'peculiar' behaviour would raise a laugh.
Like asking several times as to where the paper recycling bin was, and after being told each time by my sister that she had it upstairs, she came down to find another recycling bin in the middle of the kitchen.
On asking my father where it had come from he replied "Well, some f***er's nicked ours !!", so he'd gone next-door and taken theirs.
This is someone who'd never swear or take something that wasn't his.
Loads of comical incidents like that, but when it really takes hold, the change is unbelievable.
Occasionally a visit to the home may result in a reasonable conversation, but most times there is no reaction at all. From the time I walk in, to the time I leave, he's just a living breathing shell.
Anyhoo, I suppose it's just something one has to experience first hand and long term to understand, so as I said, no worries matey.