She wouldn't have suffered Mark
By the sounds of it she was quite 'out of it' anyway, so she wouldn't have felt anything
Its so hard when they deteriorate so suddenly, but you have think of the positives, you managed her condition wonderfully, and without such amazing care, she would have given up long ago. She loved you both
and she only started to give up when her body was failing her too badly for it to cope, and you did the kindest thing you possibly could in relieving her any further suffering