Write her a letter. Set out all your financial circumstances and state what, if anything, you are able to afford to pay by way of maintenance for your child.
Implement the new arrangement including ceasing payment altogether if that is what you want to do. Notify her that you are doing this.
When the Circuit Court action comes on, produce the letter(s), represent yourself and explain your circumstances to the Court. The Court will decide what if anything you should pay for maintaining your child.
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