Andy -
Your return to tennis sounds very much like mine. I essentially stopped playing in the spring of 2009 due to problems with my shoulder and hip. I had shoulder surgery in September, 2009, and was told no tennis for 1 year; then I had my LBHR in October, 2010, and was again told no tennis for a year. So, it wasn't until this past spring that I resumed play. Frankly, I felt like a total klutz. Timing was way off, movement was like an ox. Court coverage had always been the best part of my game, so it was pretty discouraging.
Well, fast forward about 5 months. A few weeks ago I had a pretty good outing, including scrambling all over the court, and one of my playing partners said to me after the match, "You're back."
Of course, I'm not completely back. And at the age of 64, I kinda doubt I will ever be completely back. But it's getting better and better, and I love being able to again track down and return shots that my opponents thought were outright winners.
Best of luck and much success to you!