Hi Nightsong...
Imo, there's no right thing or wrong thing...
Except one right thing: compassion. But in the right order...
First, for yourself. Seriously meditate (often, and especially now) very lovingly, and with compassion, on the little girl in you.
If one person's experience around this helps...I found I can visualize this by talking myself through it not vaguely but very step-by-step. Like a "how to". First, I orient in what I know. I know how to feel empathy and compassion for other people. When I open to it, it's like a warm beam (or sometimes, when I'm worn out, a tepid cord) going from my heart outward, in kindness. I feel a mix of love and pity (the classical, not condescending, sense of "pity") toward another whose suffering I see. Out it flows. Doesn't harm me. Doesn't fill or empty me, it's just doing what compassion does. (Bigger than my ego, like...weather, a form of energy, that's all. May cause an ache, or tears. Or like lightning, even heartbreak. But it's all weather, energy, doing the natural thing. Moves through. Changes.)
Okay, so. To have compassion for myself, it usually takes a bit more work...so I visualize the beam of that warm kindness. A kind energy and light, that cord. Almost see it as a "floodlight" (there I am, Junior Lighthouse, beaming away, out to the world...). Next step, I turn the light around, around, keep going, all the way around until it is aimed back at my own heart. And bathe in this kind light. 5 minutes is fine. Really a long time.
You got 5 minutes a day?
Then...I found I could turn it back around, and aim it at my Nmother as she was getting ready to go...
I think that practice, of intentionally meditating on loving yourself, might free some up for her. (And if it doesn't that only means it doesn't. That's okay too.) Whether you demonstrate it outwardly or with any particular action or not is not the point...there'll be weather, either way. It's okay.
If you're trying to think of what to say or do and you have decided to see her, and if you are wrestling to see if you can feel any compassion (or want to), another place to investigate that that can make a lot of sense near the end of life, sometimes more than any narrative or word-related or verbal thing...is touch.
You may find a way to touch her, for a moment or so, that allows the cord to unfurl. (And if you don't that's okay too. It may never happen or it might happen ten years after she's gone....as far as the universe is concerned, it's all the same.)
For me, it was just lightly rubbing circles on her back, when she could still sit up. I didn't go on and on with it. Just did it a little bit now and then, kind of a quiet brief thing. But I noticed it eased me, felt right. She didn't react much. No melting. Didn't matter whether I could see something, since I wasn't worried about whatever did--or did not--come back. It was a one-way beam. That was fine. I was doing it because it settled my own heart. It felt better than blocking my need to love.
Wasn't drastic, wrenching, anguished love any more. Just a beam. Weather. Cord.
I don't know if this is a way of managing what you and she are going through, the separate places you are in (and must be, on your own points on your own paths) ... but if you are drawn to the notion about compassion, I hope this example of how it happened for another child of a dying N, helps if it can.
That may not be a good path for you -- I can't know for another. But it's just what came up when I read your post.
This is a hard chapter. But strangely, healing things are possible, even now. In your own way, you'll find them.
with love,
Hops