TLDR: When I'm not yet fully the captain of the ship, how do I prevent destructive behavior in my wife (that affects the family) without resorting back to beta behaviors like pleading, explaining, rationalizing, bargaining, ultimatums?

Hello MRP friends, it's me again with another question for the forum. Brief background: I'm a career beta who is around 6 months into the MRP journey. I've completed NMMNG and MMSLP, currently reading WISNIFG and Rollo's TRM. Have read through some of the sidebar and found some amazing posts by MRP veterans. Started lifting 3 times a week and working on improving style. I'm 36M, wife is 39F SAHM, two young kids. Wife was my first and only girlfriend (oneitis), so I have minimal experience dealing with women. This post by SorcerorKing describes me to a T:

Career Beta is by all measures in a sorry state. For his whole life he has been a Nice Guy: he has done what others have expected of him; he has put the needs, happiness, and desires of others above those of himself; and most generally and importantly of all, he has sacrificed. Like many a Nice Guy before him, he has created covert contracts with his friends and lovers, expecting that his sacrifices would be recognized and rewarded. When this does not happen, he seethes with rage, sometimes openly, sometime secretly. The result is predictable: he alienates friends, he repels women, and he bewilders family members... Let’s be honest: the outlook of the Career Beta is bleak.

Note 1: Reason this and my last post have not talked about sex is because wife has broken her arm. Trying to keep up with the kino, seduction, etc. in the meantime.

Note 2: I'm not looking for a "cheat code" to each situation, although it may appear that way. Beta behavior has been so ingrained in me for the last 30 years that any advice, no matter how trivial, has been extremely helpful for me in trying to internalize concepts and put myself in the right frame of mind. To use an analogy from the comments in my last post, I'm not asking for a bandaid for my leg that has just been blown off - I'm trying to avoid getting my leg blown off but I don't even see which way the missiles are coming from. I'm getting smoked before I even have a chance to react.

First, some good news about progress. I think I'm finally starting to "get it" about STFU, and to not GAF about what my wife thinks of me. I mentioned last post about my wife's overspending behavior. Thanks to comments from others (especially u/Remington-Holmes), I realized I was letting my wife step all over my boundaries regarding finances.

Previously, each time she would overspend from her credit card, I would step in to erase her debt. I wasn't doing this willy-nilly - each time, I made her promise not to do it again, that she would try her best to maintain a budget, and that as a way of accepting responsibility for her mistake, she would agree that my help would be considered as a loan and not a gift, to be repaid in monthly installments over the course of the next year (she doesn't work but gets an allowance from me for her own spending each month - so the "repaying" would just be me giving her less allowance). And obviously - that never happened, and the debt would eventually be forgiven only for the cycle to repeat anew a couple of months later.

Then, I came across Biffault's Law. Fucking Biffault's Law. Together with reading other MRP materials, something finally "clicked" in me. Cue lots of anger, of being used as a BetaBux, of feeling betrayed by my wife's broken promises, of being defrauded by seemingly deceptive/manipulative feminine behavior that can promise one thing one day but do something else the next. This post, also by SorcerorKing, was very helpful in understanding and dealing with this anger.

Therefore, I resolved to never repay my wife's credit card debt again (something that I've told her many times before, but I really mean it this time). I also, for the first time - decided to relieve her latest round of debt to me (around $10K) - with no strings attached. No commitment to do better, no repayment plan, no exchange of money for the promise of weekly sex (that actually happened - I mean the promise, not the sex, showing how pathetic I was previously).

When I told her that I would relieve her $10K of debt to me as a gift with no strings attached, her response was, "OK". What? WHAT??? I mean, okay $10K isn't a huge amount, but it's not nothing. I wasn't expecting a blowjob right there and then, but didn't that warrant at least a "thank you" or a kiss on the cheek? I took a deep breath. I kept my mouth shut. I fought down the desire to ask her why she wasn't more grateful for my help in taking care of her problems, why she couldn't show more appreciation for me. I was successful this time in STFU, so some progress has been made.

(I also told her that I was serious about not repaying her credit card debt this time, even if she were to fall into bankruptcy I would not care. I meant to say that as a warning, but not sure if I should have said that.)

My question to the forum is, how do you manage to maintain frame/IGDAF with destructive wife behaviors? Obviously I'll do my best to maintain my boundary this time and not repay her credit card debt, but at the same time, I don't want debt collectors showing up on my door due to my wife's overspending. Can I force her to give up her credit cards (how?) and only spend in cash? Giving cash isn't a perfect solution either, she needs cash to buy groceries/food and I can't realistically monitor every purchase that she makes.

Another similar situation that recently has come up: we finally managed to find a live-in housekeeper/nanny that my wife was happy with. This freed up a lot my time, and a lot of my wife's time, so that we were both more relaxed and happy. We could have date nights any time we liked, and neither of us had to do any household chores anymore. But now my wife is suddenly mad about some trivial thing (it's not important) that the nanny did and is taking the first steps towards firing her. I tried to IDGAF and tell her "I don't care, but if you do fire her, I'm not going to help out anymore than I am doing now because this was your decision". She says she doesn't care, but I know that if she does follow through with it and fires the nanny, she's going to eventually complain and guilt me into doing more than my fair share of work, because it's happened before. I could stand my ground this time and say no, "I'm the breadwinner and you're a SAHM, you should be doing most of the housework and childcare", but since I work from home, I'm worried it's going to lead to a toxic environment at home where she resents me for not helping out even when I'm present at home (but working); again I know this will happen because similar things have happened before. A little bit of stress turns her into deeply negative and critical woman, and plus without our live-in nanny it would be much harder to schedule alone time for us anymore so I worry that our relationship would suffer as well. Obviously, I want to keep this housekeeper because it's the best one that we've had, and want to convince my wife to also keep her for the good of the family and our marriage, but I'm not sure how to do it without resorting back to my beta behaviors of rationalizing and pleading, especially because it makes her feel like it's going to be a "me + nanny" against "her" situation [nanny is unattractive so no competition undertones]. This live-in helper is the best that we've ever had, I'm not sure if we'll find anyone as good as her if she is let go.

My broader question is this: how do prevent destructive behavior in my wife without resorting to beta behaviors like coercion, pleading, explaining, rationalizing, bargaining, ultimatums? I mean I know I need to 100% be a better leader but if she doesn't follow in a particular instance, how strongly should I try to "correct" her, in order to avoid more disastrous consequences for the family? I don't have the frame to force my family into the direction I want to go just yet. And when our lives are so entwined together, and with the young kids, it's hard to make my wife take "personal responsibility" for her errors without the entire family suffering together. I understand that I can't be her savior/white knight each time but I also don't want to put the family through unnecessary stress.