My mother used to do this too.
I started working out in the garage while my clothes were being washed or in the dryer so i can watch my belongings.
If she would throw something of mine away, then something of hers shall “go missing” too.
I also installed a lock doorknob on my room door so my mother couldn’t snoop inside my room any more.
She was livid but i didn’t care. I just lock my door always and she couldn’t bust inside my room to yell at me no more.
When she yelled why i got it, I told her, “i got that lock incase a thief breaks into the house and tries entering my room.”
She was furious but couldn’t argue against it lol