It is absolutely controlling and manipulative. If you don't want to talk about anything other than D4, don't. But don't attach a verbal condition to it to be threatening. Do it because it is your boundary.
If you truly feel like it is the time to split finances as you are divorced, then do so. In a fair and equitable manner. But do not add "I'll pay more if you decide to work on your problems"
You keep saying you are done, then try to find a way to manipulate her into doing what you need to make it work. That is going yield some pretty undesired results.
