Stepmother has had a stroke; anxious for her life.

I don't know where to start; my stepmother married my Dad in 1971. She is a kind, understanding, honest, and beautiful person. Sunday, she usually goes to church; when she didn't show up to drive a group of friends there, they opened her door to her condo and found her on the floor of her living room. It appears that she had to stop taking her warfarin (blood thinner) to have a cancerous skin growth removed from her hand. Consequently, this stoppage of her warfarin caused her blood to form a clot which travelled to her brain allowing a blockage to form. When she arrived at the hospital, she was unconscious and breathing on her own. However, she cannot swallow as the clot has impacted that part of her brain. I have been sitting by her side as I watch for signs of consciousness. She is two months shy of her 90th birthday. I am extremely anxious as this person has been a touchstone for me since I was thirteen. That is a long time. If I lose this person I will be totally lost and will attempt to anchor myself to someone else who may not be so good for me. The anxiety is driving me utterly up a wall. I can't lose my stepmother, friend, and touchstone. I am lost in the darkness like she is.