Hi there ... Sorry to hear your dad's diagnosis ... The only thing I can help with is, my sister has dementure and she got slowly more confused ... I found when she was corrected by someone , she was even more confused ... We just learned to be where ever she was at that moment in time ... I now go into her world where our late mum and dad are still here ... We just say, mum's at bingo... Dad's in his allotment ... She thinks her late husband is still here so I just say, he phoned to say he'll be late home from work because he's doing overtime ... 

She's happy with that ... And we're o.k in her world too ... Hope that helps ... Chrissie x

Thank you for the reply. I don’t mind going along with it however it has come on fairly quickly and he is still leading a fairly normal life obviously bar hospital appoints and medication. The problem being is he still working part time in his own retail business and he’s insistent that he wants to carry on as he would get bored at home but the confusion ihas become so pronounced in a short space of time that it’s probably time he stopped working. But how can we explain this to him when he thinks he’s fine?