Quote: I will bring up the financial stuff with her.
My advice FWIW is don't do this. You're playing her game when you engage in this type of dicussion. Unless you do it the way honeypot suggested by getting in her face, telling her how the cow ate the cabbage, and walking away.
My late husband (as I mentioned) was married to someone like her. Early in their marriage he asked her to take over the money, and she carefully watched every penny over the years. After 25 years of marriage, he was a rather prominent executive, and she was still doling out a $40 per week allowance. She had a bunch of money rules. One of them was she would not talk about money after dinner. He was diabetic, so they ate promptly at 6:00 when he came home. So they never talked about money at home. If he wanted to talk about money, he had to call her from work and talk on the phone. If he brought up something at dinner or after dinner, like "I'm getting a bonus next month, let's go to Europe," she'd hold up her hand and say, "I won't discuss money in the evening."
But I had ANOTHER friend who was married to a woman like your W and he always kept thinking he could change her mind about stuff. He would keep talking to her, and reasoning with her, to no avail. Once I asked him to think back and try to remember if she had EVER changed her mind in response to one of his carefully reasoned arguments. He had to admit she NEVER had. And yet he was still trying to get through to her.
You've HAD the $$$ discussion. That hasn't worked. Try NOT having it. Time for a 180.
The idea that your $15 lunch broke the budget would be hilarious if it weren't so pathetic.