It helps if other family members are willing to share in this important care. My sister lives in Canada and the "burden" fell very much on me at 350 miles away to organise care and visit every half term/school holiday, even weekends when I would drive up on Friday (accommodating Head) stay saturday and drive home on Sunday. Sadly, at the last although my sister had actually flown back from Canada and was with me and my father when he died, she did not feel abe to stay and be with me for the funeral, leaving me to do all the aranging alone. Alone was very much how I felt too, especially when I took 2 urns of parents' ashes to the cemetery and buried them on my own.
On a more cheerful note, when our beloved labrador had to be put to sleep, it was handled very tactfully and caringly by our vet and Islay went to sleep in the arms of the person she loved and trusted most in the world. On coming home, I told DD how peaceful an end the dog had had and said one could not wish for better oneself. "Well Mum, when the time comes and you feel ready, just let me know and I'll pop you over to the vets"