I feel there is very little we can do individually to change people's minds or turn them away from fascism, or even to get them to stop turning their own brains into soup, but you can still show them there are consequences to their actions.
Telling my own friends / relations what I think of them and cutting ties with them has done nothing to bring them back in line with normal human values, but at least I am not burdened with the guilt of my association, and maybe one day enough people will cut them off that the loneliness gets to them and they begin to re-evaluate their lives.
It is literally the least I can do. Any sadness I felt was heartbreak that they could be so shitty to begin with.
This, i almost ghosted my best friend 7 years ago because of the refugee crisis in europe birthed a ton of arguments between us and i really started to hate his guts but thankfully he did his due research and now at least acknowledges that most of the world's troubles come from capitalism and the US empire. I don't feel like i need to cut off the people who i still dont agree, i just keep them at a safe distance.