Sorry to hear of your wife's fall Trevor... Hoping she gets well soon...
My step-mother is currently the carer of her 21yr old special-needs daughter (my step-sister), once when i commented on how it must be hard for her, she commented that "seeing her face light up as she does or experiences something for the first time makes every arguement, tantrum and screaming match more than worth it"...
Personally, i think that, not only are the carers themselves a rare breed, it takes a special sort of person to make every moment of the care they give seem worthwhile, and the smallest of rewards seem invaluable.
Best wishes to you and your wife Trevor, be patient and look for the rewards, theyre there, and they'll make the recovery easier for you both.
Davin