Life and Death and Everything in Between

My 82-year-old mother's physical health has begun to decline more precipitously in the last several weeks. Though there doesn't seem to be any unusually imminent cause for concern that she is dying, she has been considerably weakened since being hospitalized for an infection last month.
After she broke her ankle in October 2019, she moved out of the condo in Arlington, Virginia to an Assisted Living Facility in the same area. It was supposed to be "temporary," until we were able to arrange for her to live with us in Front Royal (some 70 miles West). But Mom - who has long suffered from various chronic illnesses - was unable to recover her mobility after the injury. Then the COVID-19 crisis derailed everyone's plans. Meanwhile, Mom fared pretty well in her private residence at the facility (assisted by its ample staff) and decided she wanted to stay there permanently.
We are used to our mother finding creative ways to adapt her lifestyle in the face of decades of various illnesses. But now - although her mind remains alert when she is awake - her physical condition is much worse than it has ever been. I am trying to prepare myself for her death (which could come in a week or a year or more), and also for whatever she may need between now and then.
I'm trying to "prepare myself," but I don't know how. For the moment, I do what I can, and then I pray. Where else can I go? Without God, the extremity of the end of life would appear absurd. Nihilism would be inevitable. Even with faith (and erudite theological explanations), it can be very hard to avoid becoming deflated and discouraged when the life of someone you love is being stripped away.
Suffering and death drive down to our very bones the tragic aspect of life, even for us who firmly believe that this tragedy is not the end of the story. 
We believe that Something Has Happened, not to take away physical death nor remove suffering but to transform them from within, to fashion out of them the ultimate ways of love, the path through which what is mortal is clothed in immortality.

God did not make death.

God became our brother and suffered death.

He passed through death and beyond death. He rose to eternal life, and we are called to join him "if only we suffer with him so that we may also be glorified with him" (Romans 8:17).

We will have much grief and many sorrows. It's part of being human in this present world. Hopefully as we grow older we value what is human more, even when we don't understand it.

The Lord didn't say to us, "Do not suffer." He said, "Do not be afraid" (see e.g. Luke 12:7, Rev 1:17, et alia).

In the hard moments, the sorrowful moments, the incomprehensible moments, the desperate moments, the final moments, God is with us.

He is with us in the anguish, the awful solitude, the flesh and blood of all of it.

He is Jesus. He will carry us through.