Hi - sorry I'm late chiming in as well and sorry you had to find us here.

It's quite common for pups to seem depressed after surgery. Our Abby, normally always a hyper happy girl, seemed SO depressed. The only thing we found that lifted her spirits was having visitors come over. She would wag her tail and be a happy girl for anyone but me and my hubby! She also just wanted to be alone. I hated to see her like that, but I let her do what she needed/wanted to. She would go out in he yard and "hide" behind our big potted plant. The vet said it was normal and sort of a hang over from the instincts of a dog in the wild to remove itself from the rest of the pack when it was feeling sick or weak. Luckily that all passed and by the time she was fully off the meds and had her staples out, she was back to her old rambunctious self.

As for "what to do next" I would also recommend the Dr. Dressler book. There is SO much info out there and it can be really overwhelming - but Dr. Dressler I think has rounding up the best of that info in one convenient spot and he really lays out the traditional and holistic options, which is great. 

Hang in there!

Jackie, Angel Abby's mom