Just a couple more thoughts:
(1) Yes, you can cram quite a bit into condo closets, storage lockers, under beds, etc., but will you be happy living in those spaces? I’ve found, after living for years in a house, I needed breathing space in my condo to make the smaller spaces feel comfortable.
(2) Getting rid of stuff is hard work. Clothes are easy, but hauling away unwanted electronics, older furniture, sports gear, tools, and kitchen appliances can be difficult because many places have strict rules about what is, and what isn’t, accepted. I’ve found the recycling stores attached to Habitat for Humanity to be one of the best places, while second-hand stores are often quite picky. If you’ve already done a massive clean out, you’ll know how hard it is to find places to take discards.
(3) The whole process of getting rid of stuff gets easier as you go along because you do get fatigued and feel overwhelmed. If you can’t decide about your coats right now, then move on to something else and revisit your coats later.
(4) And, last, but not least, be careful about wine and friends as “helpers”. That kind of culling is great when you have the time and energy to laugh, reminisce, and ponder item by item. If you want to seriously downsize, you need to be able to roll up your sleeves and make decisions. Yes, you might have to replace a toaster you threw away in a fit of craziness, but a $25 replacement is not the end of the world. Having other people say “But I always loved that ...” or “you might be sorry...” doesn’t help, nor does feeling resentful seeing something which holds memories being cast aside as “junk” by someone else. YOU need to decide what is important to keep without having to justify your decisions to others.
Good luck, stay strong, and have that glass of wine once your vision clears and you climb out of the pit!