Elusive,
but what about after meeting her - drop her a text everytime saying you had fun?
Nope. Other than the first time you had sex with her, this isn't really necessary when she's regularly coming to see you.
in the middle of the week - anything?
If it's to set up your next meet, sure! Otherwise, nope.
If she engages you, I would probably engage back with her, but send texts sparingly and don't get into long, drawn-out text conversations with her lest you accidentally lead her to believe that she can become something more than just a casual sex buddy!
- Franco