Hi NelliePig and welcome! 
Sorry to hear about the diagnosis and the effects. That sounds like a very sensible reaction and plan, and you’ve got off to a really, really good start! Keeping a cluttered home clean and organized, takes up a ridiculous amount of time and energy.
Put glass doors on my shelves (Ikea Billy) and ensuring small decorative stuff lives there, cut down dusting. The Really Useful filing boxes - for keeping paperwork in one place tidily, just remember to go through them periodically. Extended handles/tubes for hoovers, grabbers, dusters, might help you? (am in a w/chair so essential)
Re getting stuff out: may not be a route you want to take, but if you have lots, and approach your council as having a hoarding issue, some allow extra dump visits.
Other options – use social media to find out where local clothing banks, textile banks, paper, plastic, wood recycling, in your area are, and separate out anything that can go to them, leaving more space for stuff only appropriate for the dump.
Less frequent, but some areas have unexpected large public bins to reduce fly tipping. (ours have just restricted what can be thrown away in them.)
If you’re allowed bonfires/incinerators and have a garden or yard, use for non-toxics.
Excess of usable clothes, furniture – there's charities and companies that will collect.
If you break stuff down enough, more will go in the bin than you think. Any friends/neighbors who might give you additional space in theirs?
Freecycle, Trash nothing, nextdoor.com, Gumtree freebies, can all be good for getting rid of stuff, along with putting things in a box outside with "Free – please take."
Boot/school fair- treat it as a de cluttering day out, not a money maker – ‘all must go £1/ 50p per item’ in huge letters, give items free to ditherers. Aim is free clearance.