The poem I Will Not Let You Go by Rabindranath Tagore conveys the powerlessness I felt when faced with the loss of Ness, with the unrelenting grip of cancer as it had finally come to take Ness away from me and there was nothing I, or anyone, could do to stop it.

The following lines in particular at the end of verse IV and the start of verse V

...

With love's assurance she only said, "I will not let you go,"

But it was time to go and alas! I went.

Who are you, my foolish girl?

Where did you find the strength to say

Words so bold and proud: "I will not let you go."

...

And fight the forces of the world with the force of love alone?

...

The girl who speaks the words "I will not let you go" is the four-year old daughter of a man who must return to the drudgery of work after visiting his home for the Durga Puja vacation. To me it speaks to the pain of leaving and of being left behind.

https://www.poetryfoundation.org/poetrymagazine/browse?volume=93&issue=4&page=1