RIP Sunny.
I just don't know how you do it. I would be a disaster if I worked at a shelter. First of all, I'd want to bring every single animal home with me. And second, it'd kill me to see any of them PTS.
You are a strong person, and are doing a great thing to try and save these animals. Good for you!! I think you are going to have a large pack of doggies waiting for you at the bridge. They all know you showed them love in their last days, because their original owners could/would not.