Don’t be embarrassed. This is a good question. 🙂 Your situation is not unique — lots of exes act out when they see a former partner happily involved with someone else. That said, his child support situation and his child custody situation are his business. It’s very important that any changes he may make — or decide not to make — are initiated by him, not you. If you become the catalyst for a custody war or a financial fight between he and his ex, you’ll be implicated, as will your happy relationship with him. Decide if you want to continue seeing him, as he is, and if you do, let this stuff go. If he asks you to marry him and your finances will be commingled, that’s a different conversation, but for now, decide if you can continue with him like this or not. I know you don’t like it, and you’re not wrong, but these are his choices. 😉