We have the best vet, and last week he reminded me of the things to look for when 'it's time'. For never having had a dog before, I wasn't sure what to expect when we moved here (and the dog came with the house), but it wasn't long before she was 'part of the family'.
Her favorite person was my son, who isn't around much anymore due to his college and work schedules (in Des Moines), but I know she really loved all of us and was happy we were around more than her 'original parents', who were very generous about letting us have her.
(they moved to town, and we're in the country, and tried to keep her in the 'new, in-town yard' one day, but it was a 6-foot fence and she was gone in 30 seconds, so the country is where she was really happy.) She was almost 14 years old. We'll miss you, Chia-Bia.