There is a Larry Niven short story, not in the Known Space timeline, that contains the line: "make it didn't happen."
The protagonist is one of the first astronauts on the Moon, and he discovers an ancient alien base. He manages to get inside it, and discovers incomprehensible machinery. It's clear that this wasn't built by man, which means that it came from a race that had solved the problem of interstellar travel. Storyline follows, but in the end, he discovers that the aliens used time-travel as a part of their exploration of the stars.
And he goes a little nuts.
Flashback to his childhood: he and his brother were playing with a Flexi-Flyer, a board with wheels and a steering yoke that you rode down a hill, just like a sled on snow. His brother, maybe really too young to do it, takes his ride, and crashes at the end. (That happened a LOT, actually.) However, instead of a case of road rash, his brother gets jabbed under the ribs by the rubber-coated handlebar, and it ruptures his spleen. The symptoms are masked by shock, and by the time his parents get him to the hospital, it's too late. The brother dies. And the older brother turns his tear-stained face to his parents, and the doctors, and he begs them: isn't there some way we can go back, and make it didn't happen?
But there isn't.
And when he discovers the time machine on the Moon, he immediately tries to use it to go back in time, and somehow, make it didn't happen, make it so that his brother doesn't die.
Doesn't work, of course.
Last night, I kept myself awake until long past midnight. If I went to sleep, then today would come; and today is the memorial service for my brother-in-law Chuck. As long as I stayed awake, maybe...maybe...tomorrow wouldn't come.
No, I didn't delude myself to that extent, although there were many times in my misspent youth that I fully gave in to that futile fantasy. Most of them were because there was some catastrophe waiting for me at school. And there were lots of times when I tried bargaining with God: please, God, just make it didn't happen, and I will serve You forever.
Last night, I somehow slipped, ALMOST, into that immature, magical thinking. I wasn't REALLY trying to reverse time, in the physical sense; but I did go back in time, in my head, to the days when my sister Wendy was a little girl, and I was her big brother who would not let anyone hurt her.
And I wailed at my impotence in not being able to fix things for her. I was absolutely powerless to make Chuck's illness and death didn't happen.
I only wallowed in that misery for a short time; I take my insanity in small doses these days. After I felt sufficiently horrible for a sufficient amount of time, I came out of Dark Scary Miserable Land, and re-entered the real world.
And IN that real world, Wendy is NOT a little girl who needs her brother to retrieve her stolen bicycle. She is a grown woman, who taught public school for thirty years, retired, and is now a professor at Wesleyan College, where she is teaching the next generation of educators how it works.
Yes, she DOES need her brother today, but not to make it didn't happen. She is not fragile. I will not attempt to shield her from her grief today; I will provide an arm for her to lean on, and I will carry THREE clean handkerchiefs today (I normally carry two), and I will allow HER to decide how things will go, and in what ways she needs my support. She is strong. She has proved her strength in so many ways it would take me pages, VOLUMES to talk about them. She is not a frail, hothouse flower, who needs me to rescue her from the least threat of discomfort, lest she faint and need smelling salts. Nope, not Wendy. She is a Steel Magnolia, in the very finest sense.
I will not disrespect her by treating her in any other way.
Peace be on your household.