Read C S Lewis. A Grief Observed
I just lost my Sweet Mother 3 weeks ago to this disease.
My heart broke 5 years ago when she first displayed symptoms. She knew then that something was very wrong and she would lash out in fear of what was happening to her.It was very sad.
Dementia is very cruel because it robs the person of their ability to enjoy family and friends. It gets to a leveling off point, but all you can do is love them and realize they still love you but are locked in another world inside themselves and are unable to do so.
When God called my Mom home it was a blessing because she always knew where she was going. The misery was finally over for her. It was for us too. You grieve and miss them long before they die.
All you can do is cope the best that you can. There are no magic pills to make it better for him or you.
Bless you. I am gonna cry now.