I Support Her Children

I have been married for five years. My wife is trying to decide if she wants a divorce. Her ex-husband owes her child support, but she will not go after him to pay her. In the interim, I have been the primary support for her and her children. If she decides to divorce me, can I sue her for the money I’ve paid to support her children?

I cannot imagine an instance where you can sue for money paid towards the support of your step-children absent a contractual agreement between you and her that she would repay you.