Tomorrow morning, we go to hospital for a surgical procedure, to fit Karen with a port below her clavicle, a direct line into a blood vessel for both input and output. Thursday they tap her precious bodily fluids for a few hours, to filter out 117 million stem cells; then they immediately turn the tap the other way and pump in more chemo. And more yet on Friday. Saturday is Day Zero, when her stem cells are returned to her to start restoring an immune system, hopefully one with better discipline, that won't be trying to eat her hereafter.
These few days are going to be the hardest, by the doctors' own admission. After that it's a couple of weeks of recovery in more or less isolation. If you're curious, look up "neutropenia". Karen gets to eat astronaut food and/or very well-cooked meat & fish. No salads, no fresh veg, no fruits. We wear masks, and she probably doesn't leave the apartment. She probably won't want to.
And then we're done, or at least they're finished with us. We come home (and trust me, you have no idea how attractive those words sound), and spend the next year rebuilding Karen's health. Lots of home-cooked food (hah!), lots of rest. A degree of care in social contact [get your flu shots, people! Herd immunity is going to be our friend, for the foreseeable future]. An ongoing drug regime for a while, but nothing onerous. Oh, and making friends with the cats again, because we will smell of the vet.