My cats are aging with me...lately, I find myself thinking how much I EXPECT them to be here...to always be here.
Long ago, I had a cat for nearly 20yrs---one day she left the house, and died somewhere out of doors. I had her in my dorm room, I have a photo of my daughter, at least 16yrs later, holding her...she travelled with me a lot when young. Sometimes she would even feature in a dream as if an independent (eg: watching over a small shop as the owner)...no one could see my reaction when she was gone...
I still can't quiet let go somewhere.
Then I think of my late brother and a cat story...oh my.
Do Grieve!!!!!!!! Openly. It will help you so in the long run...