For years I worked with people who needed to declutter their homes, for many different reasons, divorce, moving house, downsizing or just because living in chaos had become too much. I am afraid that actual 'hoarding' is a genuine and all too real problem that can only get worse if not tackled. It is the hoarder who needs to firstly, acknowledge that it is their problem and secondly to begin the long, slow process of letting go for themselves. Simply 'tidying up' a hoarder doesn't work. However there are people who don't know how to keep tidy. My son has difficulty organising his life. Simple 'how-to' lessons work well here. Hoarding or being attached to objects is a condition where everything has meaning and is considered to be important or necessary. People do try the 'one-in, one-out rule', the 'keep it in you own space' rule and sometimes it works, it gives structure to someone who feels chaotic. But actual hoarding is a mental health issue where the person may need outside help to deal with inner problems. Getting your DH to ADMIT it is a problem is your goal! All that said, it is his home too and maybe he just wants it to feel that way by surrounding himself with familiar things while he is grieving. His things are his comfort blanket, for now