I'm the grand-parent comment so I feel a bit responsible for where it went so maybe I can clear what I meant here.

My view on the question of impermanence has been shaped by buddhism. I'm not a buddhist, I just discovered buddhism at an age and in circumstances where it talked to me and helped me a lot going through some very bad stuff.

In a nutshell, but the subject is extremelly vast: https://en.wikipedia.org/wiki/Impermanence

I hope it explains better than I did what I meant by "nothing is permanent", and maybe it'll be of interest to you like it has been for me. Feel free if you want more pointers.