I'm so sorry that your Taffy passed away.
I had a very similar thing happen to me. My mom got her dog GiGi when my dad passed away. When my mom passed away GiGi was 13 years old. I took GiGi into my care and had her for 3 years. I had to have her PTS because she had kidney failure. So, I know where you comming from, I not only felt so.... bad the day I took her to the vets for that but I felt she was the only living bond that I still had with my mom and now that was gone also. Time does really help the pain your feeling now. And you did not ramble on. We are all here to listen and to share our experiences.
