In this case, I would be your wife.
However, every relationship is different, so take this with as many grains of salt as you feel are warranted.
I grew up much like your wife (and you, it seems).
The lowest cost option was always it, because better options were never available. You can take the girl out of poverty, it's harder to take the poverty out of the girl.
One tact you might try is showing her that a rainy day fund, does, indeed, exist. She might be anxious that the costlier options are making you more vulnerable, in case disaster strikes. If you can demonstrate that is not the case, and that the choices are actually making her MORE secure, that might help.
For decisions you make in the future, be sure to explain your reasoning. And, at least try to make her feel included in that decision, that should help her feel better about it.
My husband is really good about doing that for me. There is such a thing as being penny-wise and pound-foolish, and I was a textbook case for it. My husband did a great job of gently educating me otherwise. Believe me, I resisted. I felt a lot of anxiety about paying off my credit cards, when we were first involved. How could I afford to live if I was spending so much money for no tangible benefit? I was keeping up all my minimum payments with no trouble. Why not continue doing that?
Also, he convinced me that buying savings bonds with some of my income each paycheck was not the best way to save. And he convinced me to cash in the ones I had. Boy, did I ever resist that!! I thought I was going the smart thing! (And, it was definitely better than doing NOTHING!) But, I have to say, he has done a great job with creating a nest-egg for us, in spite of my initial misgivings.
About the health aspect: It's another thing that makes her deal with her anxiety head on, which is not what anxious people want to do.
Also, if food is a comfort for her (as it is with many overweight people, myself included) "giving it up" is very anxiety-triggering.
What will I do if I can't have my treats when I feel overwhelmed?
"Eating your feelings" is a real thing. Again, positive reinforcement is a tricky balancing act. Maybe invite her to take a walk with you, rather than going to a gym? (Gyms can be VERY intimidating for those of us who are not body-positive).
Go on bike rides together?
My husband and I take yoga classes together, which really help to relationship build. It's kind of a built in date, and we get a healthy dinner together afterwards. Also, something about yoga helps the libido as well, so, sexy-times sometimes ensue later in the evening.
Anyway, I don't know if any of this helps. I just saw a little bit of myself reflected in what you said about your wife. (Although I've never actually yelled or thrown things, I'm more of shut-down and sulk kinda gal).
Good luck!!!
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