Thank you so much Donuel and Charmion. Your posts comforted me a great deal.
I have to try and concentrate on the happy life Smokey had - 18 years of good food, nice 'friends' and always access to the open air and the garden, plus loads of care, love and affection from his two-legged servants.

Sam the Skull is still around at the front of our house, and little Binky peering through the conservatory windows at the back.

My sister (who also adores cats) told me to get another one immediately, but it's too soon and we need to grieve first.
Anyone who loses a much-loved pet has to go through this, and only time heals the sadness.