If she asks again:
"Do you have that $XXX you owe me?"
That might put the brakes on her eagerness a bit.
But in actuality, the answer should still just be "No. It is not going to happen."
What if she gets the idea that paying the $XXX would be enough to make her welcome to move back in and mooch her way past what debts she's "paid up"?
This reminded me of a funny(ish) story of how a college buddy of mine dealt with a similar moocher... here is the abbreviated story...
Moocher lived with my Buddy for a semester or so, then vanished for several months, owing Buddy lots of $$$ for rent, utilities, groceries, etc. Moocher then showed back up at the end of the school year and wanted to move back in for the summer.
Buddy: No. Besides you still owe me $$$ from last time you were here.
Moocher: What if I paid you back?
Buddy: If you pay me back the $$$ that you owe me, then I will reconsider letting you move back in.
Moocher pays Buddy back in full.
Moocher: So, I can move in?
Moocher: But you said you would reconsider!
Buddy: I said that I would reconsider my answer. Not change it.
OP, maybe you should try this script next time you hear from your moocher?