As we look forward to 2020 with new plans and dreams, it's a good time to reflect on past successes.
I asked this question of my DS last night, and when he turned the question back on me, I had to think about it for a moment, but then I determined that unequivocally my biggest accomplishment was downsizing: specifically, getting rid of 2 tons of crap. It was a huge task, but we committed to it, and DH and I did it without too many arguments about what to pitch and what to spare.
The Purge will have have lifetime positive consequences for me. I feel I've grabbed at least one brass ring of the the simple life.