can you explain to your son that you can't afford to maintain him and his father as well? he probably thinks thinks that his father can't find work or for some reason like health, is unable to work.
explain that if that's true he should be getting disability, and that even though you don't have to give over money, you are happy to, but the money is for your son, not for the new family. if his father can't afford to keep him, the young man should be with you
where the court felt he should be anyway. it might be a hard lesson for him to learn, but he has to learn that we can only live the way we can afford to, not the way someone else can afford us to. he can still visit his father whenever he wants to.