Seriously though, there is a difference between hanging on to some junk/stuff or being a gear addict (my problem) ... and REAL hoarders who cannot let go of things to their and their family/friends' detriment.
Very recently we saw a television series called Hoarders - or similar. It was very VERY sad. People who hoarded pets, trash, old food, paper, ...
Some of these people were seriously considering suicide.
The real thing takes an expert - just like any other psychosis.