Pete,
I take it you ment that your shoulders flexibility and stability will never be as good as before the injury. That is entirely possible, but strength is so much easier to do something about. Are you able to do dips, handstands and pull-ups? If not, those exercises + front and back levers performed on rings are superior to anything you do with apparates or free weights. The instability of the rings and the multi-plane movements/resistance will train all the small muscles and their coordination in a much more advantageous way. I spent many years climbing and busted both elbows and both shoulders (overreaching, hanging off the joints, not taking rest when I should => chronic tendonitis etc). Working the rings is what have rehabilitated me.

If your gym dont have rings, ask them to install a set. I can give you references if they need. Rings are superior for upper body workouts and you can build strength gradually through progressively harder exercises. Nobody pulls the moves you see at the gymnastic events the first day And you are never too old to build serious strenght, it just takes longer due to less hormonal activity and the correct diet.

I know I sound like a "besserwisser", sorry, but the intentions are all good (and this is something I have become passionate about. I have my own set of rings installed under the staircase).