Thank you my friends.
Exile, her condition has been mostly stable for the past eighteen years, kept that way by the right mix of chemical 'rebalancers'.
What we think has happened is that the medication she has been taking for an onset of other physical conditions has messed up the equilibrium.
This is very hard on my dad who has not yet recovered from his own brush with the Reaper not so long ago and doesn't have the strength to carry this like he once did.
As a family, we have all confessed to each other that we never thought we'd be facing this horror again. I don't mean to diminish those who have experienced real, physical, bereavement but I think those who have encountered this will understand when I say it is like a death but a human who looks like the person you knew is still there in her place.