Well I would say that your W wanting to leave to date another guy is a pretty damn big financial irresponsibility.
It comes down to this...the money is for BOTH your lives and your kids'. Not just yours and not just hers. All you're doing is protecting that.
You can't control the storm that your W is kicking up. But what you can do is lock the storeroom (finances) shield your kids and buckle down until her storm ends. Her storm will get worse with things flying around, dark skies, thunder and lightning, etc. But you are BigJohn. You are the rock that will not be moved no matter how bad the storm is.
You know what happens to things when they try to go head to head with a storm. They get blown away. And that's what you've been doing with your W. Instead, do the opposite and let her rage, not you. Let her get upset, not you. Let her seem like the idiot, spoiled teenager, not you. In the future, when your kids look back at how you acted now, you want them to be proud and say "that was my dad"! Just think how they're going to look at their mom. Makes you want to laugh.
M-43 W-40 2D - 9 and 5
Emotion, yet peace. Ignorance, yet knowledge. Passion, yet serenity. Chaos, yet harmony. Death, yet a new life.