Mom’s been actively dying for over week now... how to comfort/awful to watch!

I am sorry for what you and your dear mother are going through.  I am a daughter whose mother is in the mid stages of a terminal disease, but it is going to be a slow and awful decline for her.  I know what's ahead and know also how you feel about wanting the end to come quickly just to stop the suffering.  Then comes the guilt for having those thoughts.  I think that's not uncommon.   

You ask about how to make it better or help her be more peaceful. When my mom is going through a tough patch, I use the sense of hearing and touch to ease her mind.  I've been told that hearing is the last thing to go.  Be careful what you say in front of her and keep her room peaceful perhaps with some of her favorite music playing softly and reduce stressful noises like sirens or yelling on the tv.  Lightly hold her and and pat it. Tell her she is a good mom, taught you a lot, and that she is loved by many (friends, relatives, neighbors, etc.) If she likes flowers, keep a fresh cut vase where she can see it. 

i've also been told that hearing is the last thing to go. i do hospice for a local cat rescue (essentially i adopt the "unadoptable") and have (sadly) worked a lot with a local in-home euthanasia dr. we do different things for the kitty who's dying, depending on what their favorite things are. but we *always* talk and sing to them, even after they stop breathing. the dr says he continues talking and singing to them as they drive away. so sweet and sad.

anyway... i also understand that some neurological changes might make listening a challenging and/or painful activity. the brain might scramble and re-arrange music and speech so it makes no sense and is confusing or distressing. even favorite music can be painful for some. it sounds like your mom might possibly be having this experience? if she seems irritated by her favorite music and tv shows and conversations, perhaps silence is what she prefers?

have you tried comforting scents, like fresh flowers, dried lavendar sachets, favorite perfumes, worn/unlaundered clothes that smell like her grandchildren or hubby, blankets that smell like her dogs or cats, coffee, hot cocoa, bubble bath, favorite scented candles, etc? you can even get as specific as, say, for example if she loved holidays maybe evergeen scented candles? if she loves hamburgers, how about the smell of burgers? (it probably goes with saying, but... if she's hungry but nauseus, that's a bad idea.) fortunately you sound VERY keyed into her reactions to sensory input, so if anything bothers her of course you can remove it immediately.

i wonder about comforting sights, too? flowers, plants, videos with sound turned down, large photos of loved ones? (poster-sized so she won't have to strain her eyes to see them? maybe even tacked to the ceiling if she's laying down?) if she had favorite vacation spots, maybe large photos from those places? if she liked birding, how about a nature video of birds?

is she sensitive to certain fabrics or temperatures? for example, if she likes cool, soft, silky fabrics maybe swing by a fabric store and find something that she'll enjoy feeling draped across her arms? if she was often feeling chilly, maybe a heating pad under her back or even on her arms?