I used to get incredibly frustrated by my mum, an Ercol furniture hoarder. She and dad bought lots with a view to buying, restoring, and selling, but they never quite got round to the selling bit, mainly because mum didn’t like any strangers in the house. Even to the extent of doing plastering rather than having a plasterer in, before she was very disabled!!
When she went into residential care, AFTER I sold some of her furniture when she was in hospital previously, she ended up with over 60 dining chairs, 10 dining tables, 10 long sideboards, 4 studio couches…etc.etc. I wanted her to get rid of the furniture in her main front bedroom (unused for many years, because it was stacked so high with furniture) so that it could be redecorated and fitted with an ensuite, but she refused. Instead, she ended up in a nursing home rather than her own home for the last year of her life, and I had to completely empty and sell everything and sell her home, a large 3 bed bungalow near Bournemouth. Where was the logic in that? There wasn’t any!
Counselling made me realise that mum would never change, she was incapable of changing. However once I’d accepted this, life became easier. I gave up trying to help her change, to get rid of stuff, to eat properly, etc. etc. It was ME that could change, not her.
Your mum and dad are similar, they’ve bickered throughout their lives in a love/hate relationship, and that will never change.