Anfauglir, I am so sorry that your mother is gone, and that the fragments of who she was reside inside of her frail body.
My advice would be to continue to take your lunch breaks on Tuesdays. It is such a small chunk of time out of your week, even though it takes a disproportionate amount of your mental and emotional energy. Try to imagine how exhausted she was when you woke her up squealing for those 2 AM feedings. Imagine those long-forgotten sleepless nights in which she sat vigil by you monitoring your scary fever. Neither of you has any memory of those events now. But YOU know they happened.
Sit vigil by the shell of the person she was, as a way of honoring the person she was.
When her body dies, I suspect that you will be glad that you gave all that you had to give.