You may discuss the finances with a L. A L should be able to tell you what you can generally expect in case of a D. You can use this as a general guideline how to approach the situation. It does not mean that if the L tells you you may have to pay her alimony, you start paying her before the D. But at least you need to know what to expect.
For you, you need to figure out where your involvement in her life stops. It is for your own good. If you cut off her finances, that will not be the end of the world anyway. She has not been dumpster diving since you stopped cooking for her, right? Let her find her own job and deal with whatever she is dealing with.
The financial matters have nothing to do with the other issue: you do not want to blame her for anything. Just cut off the money, and do not tell her anything. If she comes to you about it, say you will be happy to reach to an agreement about the money and leave it at that. You do not owe her agreement on any subject which is not directly related to your kid. Let her figure things out.
Why do you expect it to push her to angrily D? Why are you controlling an abusive?
