Well done.
Scan photos. Save them in the cloud, and share them.
Think - is this difficult to replace? If so, take a pause, and come back to it the next day.
Books (my weakness) can usually be replaced.
But honestly, the rest of the stuff? Get it sold.
I'm in a similar position, if the mirror of you - we moved back to the UK two months ago after 21 years abroad. I'm set up in my new house now, and am bracing myself for the delivery of a 40' container of our belongings from Qatar. And I know that I will open half of the boxes, and wonder to myself - why did I keep this?