It takes courage to write about such a difficult time. Even if you witnessed dementia diminishing your dad's life, little by little, nobody is fully prepared to experience the loss of a loved one. Hope writing about it is cathartic and will help you to accept the situation.
Thank you for your kind words and sentiment. Yes, even when the end is expected it still comes as a shock. It is something we will all experience at some point or another, and one most will never get used to.