My mother used to do this with our things. My things, as a teenager...
I actually deeply resent her, partly because of this. She had no concern about whether anyone else in the house wanted/used/cared about the item in question; she just wanted to throw things away. Some of the things were treasured, from my late great grandmother, incredibly valuable, etc.
I declutter, but do not throw out anything of value. That will change soon, when we move from out 1600 sq foot house to a 1000 sq foot apt.
ETA: Not that anyone here is ruining their relationships! I just realized how negative I sounded, didn't mean to, just ruminating.