It's a strange feeling being told in no uncertain terms that the 'lifespan' you had expected, would not be as long as you thought, and it is almost like the Doctor stood up and punched you straight in the stomach...
It initially triggers certain instinctual,
PRIMAL instincts to do certain things... drink, eat, fuck, spend - the list goes on into what can only be classed as debauchery... and then comes the true realisation that it was the pleasurable things that got you into this predicament in the first place.
It would be nice to say that it brings about the revelation that what truly matters are friends and family, but you find yourself pushing away from all outside involvement, believing that you have become a burden, or in extreme circumstances, a shame to them.
The denial stage of the Kübler-Ross model isn't as long as you would expect either... every Google search you have made shows the same result - life with a progressive disease just doesn't last as long, and in the rare case that it does, it's not a happy life... so you then skip the next 3 stages and move on to acceptance.
You accept that you will not get to fly on a Virgin Galactic sub orbital flight, you accept that you will not get to see first contact with another species, you accept that you will not get to see your favourite Hockey team... the Phoenix Coyotes ever raise that DAMNED Stanley Cup and you do what you do best... which is to live your normal, detached life and know that when you are gone, you HAVE left something to remember you by... people just don't know it yet.