Oh, hoarding....

My mum and dad were both hoarders. My father died, and my mum has remarried, to a hoarder.
My dad was the "I could use this" type. He worked as a builder, so always had left over materials, scraps of wood, screws and nails, a saved window, a salvaged door.
The problem was he was so messy and disorganized, stacks of boards would rot, windows got broken, coffee cans of screws got water in them and went rusty, hammers got misplaced, and he was always talking about cleaning it up when he got a chance. 
My mum is a combination of sentimental and useful hoarder. Every plastic bag, yogurt pot, piece of string, tea cup, whatever, has to be saved. Books she will never have time to read, magazines, old clothes that haven't fit for 30 years, old cards, plant pots, it just never ends.
I have tried to talk to her about it, but she gets so angry and defensive. She has other MH issues, and I wonder how much of a role that plays in it.
She and my father were both raised after the war, in super neat and tidy homes. My poor grandparents were forever saying "But I didn't raise you this way!"
I think for my folks it was a combination of things. They don't like to see things wasted, they want to be practical money-wise (although they have never had a spare dollar), and perhaps not being able to keep everything when they were younger made them rebel as adults.
I think my mum worries that if she doesn't keep a physical object, that she will forget the memory or emotion attatched to it.
I could have been a hoarder, and certainly had leanings that way.
When I look back at photos from when the kids were little, I am always shocked and embarassed by the mess in the background. 
That was part of how I stopped though. I kept taking digital pics of areas, cleaning and organizing them, and taking new pics. I made my own privet before and after slideshow. When ever I started to think that things might be getting bad again, I went back to the photos. Seeing the real difference helped me stick to the changes. My house is a heck of a lot easier to keep clean, I no long feel anxiety when there is a knock at the door, and I can comfortably have guests over.
Sorry, that was bloody long