Further Proof of the Inscrutability of Cats

We have a cat who was a rescue from a litter found under a porch.  All of the kittens ended up small (in the 4 pound range as adults), black and white tabbies.  As far as we know, she’s the only one left of the bunch.  This little cat’s name is Sterling, or Ling-ling.  At this point, she’s an old lady, being at least 15 years old, but still spry, and even nimble when it suits her.
When I was ill last year, she took it upon herself to be my guardian, lying on or near me all day and even following me to the bathroom and waiting outside the door to make sure I made it out OK.
Once I started to sit up for my daily meditation practice, I noticed a peculiar phenomenon:  once I had arranged myself and the practice had begun first steps of settling the attention (and *only* then), Ling-ling would creep very softly into my lap and curl herself into a warm little ball.  She would often do this so skillfully I would not be distracted by it.
This in itself isn’t too much of a puzzle (it is a lap, she is a cat, and I believe there are rules about that), but there is more:  almost without fail, when I entered my ‘cool-down’ phase of coming back into consciousness *but before I had begun to move or shift in any way*, she would get up and walk away.
We referred  to this with good humor as Sterling’s Ride-Alongs (Win-win.  Meow-meow).
Sterling, or Ling-ling