How to educate my financially-averse spouse

tldr; My spouse, who has always been a huge spender, has asked me to help her get her finances in order and to educate her financially. What can I tell her? Where do I start? Which topics should I cover and in which order? Any books she should read?

Longer story: using a throwaway account since I am talking about my spouse. My spouse and I both have similar education, very similar jobs, and very similar salary. She is the spender and I am the saver. We have combined finances for everything, except discretionary spending, which is separate. So mortgage, gas, groceries, any health-related expenses etc. come from our joint account. We have a budget, but there are always "necessary things" and we end up not following it. I complain every month and she has to return some things. There is tension in the system (probably the thing about us that stresses me out the most), but in the end we do get along. We (or maybe I?) have financial goals and we are more or less on track to get there, just not as fast as I would like.

We do have separate accounts for discretionary spending (clothes, our own entertainment, etc.). It is an absurd amount, $1,200 each month for each of us. While I have managed to save/invest about $25k over the years (plus open and fund a 529 for our daughter) she ends up every month with $0.

Now her dad needs a hearing aid he can't afford ($900) and she wanted to pay for it herself, but she can't. To be clear if this was a life-threatening emergency I would of course chip in, but this is more of an inconvenience.

She has asked me to help her get her finances in order. I think that more than that she needs to change her relationship with money and understand how it works. She has not had any financial "culture" growing up, and related or not both her parents (divorced) are not in a great spot financially. I've been extremely lucky that my parents did give me solid advice over the years.

It is one thing to know what to do and it is another to teach. Every time I have tried to discuss this I have been met with boredom. This is the first time she has actively seeked advice, so I feel like this is an opportunity I cannot miss. We have agreed to take a look at this tomorrow evening. I think we'll need many sessions to get her where we need to be, but I am feeling optimistic.

Where do I start? What do I tell her? If there were some sort of plan or "curriculum" somewhere I could follow that would be amazing.

Thanks in advance!

Edit: Thank you all for the responses so far, please keep them coming! Need to log off now, but I will read them all in the morning, I appreciate each and every one of them.