Wait, Ariel Sharon is still 'alive?'?

Wow, that's horrible. I can't imagine a worse fate than being in a permanent coma for years on end. Why don't they just let the poor dude die? I put it specifically in my will not to animate my corpse with tubes and machines if I can't live on my own. Why are they still dangling Sharon's corpse above the grave like some sort of marionette?