uncluttering one day and one thing at a time

That's hard. Maybe for the stuff that's in good shape, you could give it to charity? To a women's shelter or something, where it could help someone else? Or Goodwill if it's not the sort of thing that a shelter would need? You'll still have all your memories that made the keepsake special, and maybe the keepsake will carry some of that goodness and positive energy with it to a new person who could maybe use some.