Hi Cara,
Sad to read about your grandma. I lost my father about 2 weeks ago to stomach cancer. Still hurting from that - and can't even describe it. He was 68. When first diagnosed this March he was given 6-9 months. But we lost him before that.
I understand 100% about the shadow of impending death. I have spent two nearly sleepless months since that diagnosis. The cancer was aggressive, and we could see him fading. We also went through this phase of not understanding my father. Towards the end he could speak but not clearly. He was forbidden even water (as his stomach couldn't handle) and perhaps that had to do with his lack of articulation.
The part about patients rallying near the end is true. At one point my father's cancer spread to his lungs and they gave him 48 hours. He managed to live for 3 more weeks. Its their willpower, and desire to live I think. He was conscious and could understand us but couldn't talk. Slowly, organs started failing and he was being sustained by medicines, ventilator etc. Then one day his pulse started fading. The pulse just faded gradually and then stopped. The end was peaceful. He had the whole family with him that time. We thought it would be scary, but it was quiet, and peaceful.
I know this must be extremely tough for you - but know that you are not alone. Be thankful for your gram's presence and make the most of your time with her. Every touch, every hug is precious. And if you believe in God, pray for guidance.
Priya.