Very sorry to hear about this. When MsM broke her tib and fib in a cycling fall it all happened so quickly that we weren't quite sure how it turned out so disastrously... but she did make a full recovery and has since done LEJoG and lots of other long-distance rides.
While immobilised in plaster she suffered a pulmonary embolism that was far more life-threatening than the fractures. She was subsequently prescribed a blood-thinning drug, but should perhaps have been given it before the emergency. This might be something worth enquiring about.
Since getting mobile again, MsM has needed orthotics, something which is probably related to the biomechanical legacy of the break (her foot not being joined back on at quite the original angle).
Recovery will probably be a prolonged process. Lots of love, encouragement and understanding will be called for!