Op, your wife is cool, the harder thing to do is come back to the bike after the 1st fall. I really cant imagine the accident because have had falls at 40 mph and no bones broken, and not only once but at least 5 times in training sessions. This remembers me a friend in LA that everytime we talk he have had a broken bone in a ride and the worse is that had been in the most stupid accidents ever like falling from a stand still or going 5 mph and somebody crash him and stuff.
U have to be strong and in the PT if it hurts u have to just make her do the stuff, u feel guilty and i hope the accident was not your fault. Things happen and she has to get up, suck the pain off and continue u know... thing that for sure u know...
Good luck again