For my 2 cents, I'd go completely dark if I were you. No calls and definately no faxes unless you are 100% definate that is what you want.
It's been a hot week for you and you both need time to cool down. I feel and sympathise with you as you have been providing for her both for too long and too much.
Your W needs to accept responsibility and to make changes. I would not expect that her medical condition limits her from seeing what her options are. It's either to change or to face reality and it doesn't sound like she's anywhere near there despite her commitment to trying again.
My W was the same as yours in the sense that she wanted more and when I gave more, she wanted even more. She was lazy, worked part time and while we didn't blow $200k, the S cost us enough. Since we have been back together, W has increased her hours to 4 full days a week and has earnt a promotion that we worked together to help her achieve. I had never at any point hinted or said outright "you should do something about that", she just saw the need. The point of what I am saying here is that until I stopped giving, W didn't stop taking and when she was starved to the point of having to cut a deal to retain her solicitors services, reality hit when W's settlement figure depended solely upon the hours her solicitor racked up.
I honestly thought that your solution of having her as an salaried employee was good enough. She is obviously not ready to accept that responsibility and you have no other choice that I can see other than to dispense tuff love.
You need to accept responsibility that in your kindness, you have been contributing to the problem. When you have done that, you need to admit that it has been a failure and implement another plan. The fact that your W believes you have stashed cash indicates there are trust issues and it is so early in the recovery of your M to expect that these issues can be fixed overnight. You obviously can't convince her otherwise so stop trying. By defending it all the time it seems you just perpetuate the suspicion.
My advise is that you don't cut her off but to support her on what you believe is reasonable and affordible for YOU. If W objects as you would expect, you need to tell her that is the most you can afford and it is up to her to make the most of it. Letting go of the cafe lifestyle and all the trappings will be hard but she has to do it.
Your W has pushed the M to the virtual brink and has come back. I would expect that she feels like crap right now and needs to wallow in her own doing.
Sorry for the 2x4 but I hope I hit you a beauty.
Suit
"It's better to have no spouse than have a bad spouse"
