That needs to be cut off immediately, along with anything else she's using to conduct her affair. Do the moves simultaneously, and then tell her that you've done it, "because I have decided that I will no longer financially enable your affair." Only do this AFTER you've done "Step 2" above.
I'm headed to bed. I hope you can get some sleep. I will tell you, although it will still be very hard, there is NOTHING like a night's rest after a day well-fought, admirably.
