i long ago lost count of my patients who died. in all honesty, the way people die is their body shuts down and they withdraw into themselves. it's impossible for me to believe they are aware of who is visiting them, etc, when they reach that condition. long before they reach that point, they're totally disoriented and neurological responses deteriorate. i realize the families often want to believe there's going to be some sort of last moments where they're alert, etc. that's only tv drama, because the reality is entirely different. so don't expect anything except seeing her with all the tubes, etc.
death is a journey to peace and a relief from suffering. it's a natural process, and medicine more often than not prolongs it needlessly. the thing for you to do is just remember all the good times you had with her, and see this as a time to celebrate her life. i know it's hard, but be happy for her, because she'll finally be free.