May I ask what kind of dog your last one was? So strange with the story of your first dog because that was the mirror image of mine. She was a miniature schnauzer as well(gray/black mix), 15, blind and deaf and just really miserable. She was very picky about those around her and unfortunately didn't always like me so I didn't have a true connection to her though and we put her down as we were moving across the country.
Our last dog, however, was one of the hardest experiences of my life. She was a golden retriever rescue and we had her since she was 9 months old. Just the sweetest thing in the world and loved everybody. She started to get really sick right after she turned 10 and couldn't keep any food down. They discovered she was suffering from kidney failure and there was nothing we could do. I bawled for 2 hours straight and my boyfriend has never had a pet so it was hard for him to understand how hard it was. It's honestly like losing a family member so I feel for you. I'm sure all of our amazing pets are up there at the best dog park ever just loving life! Prayers to you and your family!!