Thanks for your kind words - they really help.
Dad is still sleeping mostly. I asked him a few questions today and he answered them slowly, but cohesively. He is aware of what has happened, but can hardly be bothered to speak, his eyes look empty, and seeing him a shadow of his former self is what hurts.
He was not in particularly good health prior to the stroke, but that said, he is a strong man both in mind and body. I'm hoping that he has the will to pull through.