Maybe a home hospice secular counselor can help you 3 ? Are your parents religious ? If she is trying to regain control of an aging body MAYBE a swimming pool or massage or accupuncture can give her some relief and respite ?

Thank her and show that she was successful
in her life and accomplishments.You value
and celebrate the uniqueness that is her
alone. Death cannot hold the upper hand;
or all we do (or did)matters not.She did change the world otherwise you wouldn't be
sharing this part in her life(hard as it is).
Death sting is we didnt matter.Share the
fear as best you can,as we all have different
thresholds of fear.We all will be where she is.
And you reflect the good she lived.We
can't fathom another's fears-just allay them.

UPDATE: Many thanks to everyone who's responded, including recently. I don't know why this post is showing up as current, because I actually made it almost nine months ago and my mother passed last September. It's too old to even edit to add this update, so I'm putting this here.