Beautiful ending, even if it's rather sad to see these two apart but it keeps in line with how you wrote them from the start.
I liked how you left an open window for them and us readers as I, oddly, got attached to them.
I'll be happy to read a new part of "the Diamond Universe" if you feel continuing that plot-line but I'm also "eagerly" looking for new chapters of you other stories (City on the River, It's Hard to be a Man, Bicker, ...) and especially your new 18th century one.
Thanks for your excellent work.