He's just mad that he has to pay money to you at all. Reality is here that even though he wants to start a new life and forget about his old one, he can't....he will forever be tied to you (as it was suppose to be because you made vows) and it kills him that he has to pay you money when he wants to forget you. CONSEQUENCES of his decision to leave you and his family.
Your lesson to your son was perfect, and even your son knew it.