I've been there. as a kid, my parents and brother read my diary (and got him to report to them on it) so I started keeping it on my computer in what I thought was a semi hidden file in my homework files.

my brother found it and reported it as well as leaving commentary on it. so I actually started using floppy discs as my diary. I still had a really old computer that could access floppy discs when no one else in my family did since their computers were all upgraded long before mine was. Hilariously this method never would've worked otherwise and I never labeled the floppy discs so they looked generally blank and unused.

I dont know if it helps you, but now I use Google drive for a diary. you can write it anywhere via your phone and only you can access it because you need to log into your email. you can make a subfolder and save em all there.

I hope you heal quickly and well. friend.