A couple of things spring to mind.
First, is your illness service related or made worse by service and hence could be classed as 'service attributable'?
Second, might there be any circumstances in which you could/would continue to serve in a different branch/trade and with a reduced medical category.
Third, could the time be used by your wife to update her qualifications etc by taking training courses or beginning a career in a completely new area. There seem to be loads of adverts for teachers for example with paid training.
You mention being out of the loop but now might be the time to call in a few favours from 'mates in the know'. Whilst these will be elsewhere, they will probably be able to give you all sorts of valuable pointers.
Old Duffer