Don't have any regrets about anything regarding this. I'm sure she appreciates everything you did for and with her. Unfortunately, there's not much you can do today to make it much easier. Just do some of your favorite things, and try to take your mind off of it.
When I lost my cat a few years ago that I'd had my entire life, I kept thinking to myself that it's going to be impossible to replace him, and assured myself that I didn't want to get another cat. A week later, I had two of them. I thought that it would just complicate things, but my parents insisted that I needed to get over it. Surprisingly, it actually made me feel a lot better.
So I guess if I had to give any advice, it'd be to let things mull over for a bit, and then you might think about getting a new dog. It won't be the same, of course, but you obviously care for your pets a whole lot, and I'm sure any dog you decide to take in would love you just as much as Cutie Pie.
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Xbox GT/PSN name: TatteredUniform
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