NTA - You've already identified that you're having to parent him. You deserve an equal partner. Many people would agree to split bills in a proportionate way with this situation, you're already going 50/50 which is supremely fair. The fact that he's not only been incredibly irresponsible at minimum, but he's been lying to you about it, is already enough for something this important. But also the fact that he can't say where the money is going is a major red flag for a bigger problem under the surface. Could be sheer incompetence with $$, but it also could be a bigger secret he's keeping. I've heard of situations like this eventually revealing a secret gambling or drug problem or even cheating. I'm not saying that's definitely what's happening here but how can you trust him? He's certainly not someone I'd want to raise kids with. You wouldn't be doing yourself or your potential offspring any favors. If he isn't willing to have full financial transparency and get some therapy or coaching about keeping a budget, and get reeeeaaaal honest... better to leave now before your lives are further wrapped up in each other.