I'm so sorry.  My almost 8 year old Black Lab Ajax had his amputation just a few days before Hershey.  We were fortunate that we didn't have many post-op complications, but even without that, I still see him improving every day.  One thing about a relatively young Lab is they just get bored, bored, bored - if Hershey is like Ajax, his favorite activities are all unavailable right now, especially if he's lost his appetite (i.e., run, fetch, tug, swim, eat, and not necessarily in that order).  We found that AJax perked up with visitors (dog walker, pet sitter, special friends) who came in with a happy voice, and also we got some new toys, though they wouldn't have worked if he wasn't interested in the food.  Anyway, rest assured Hershey's normal personality will return - he is a Lab, after all!!  In the meantime, I enjoyed looking at some of the videos on rehab and dog massage on this site - it made me feel like I was doing something, and gave me an activity to work on that didn't require much exertion on Ajax's part.  Good luck, sending happy Lab vibes your way