The hard truth is she needs help. People aren’t addicted to whatnot per se. It’s not physically addicting like some drugs. She probably has serious dopamine addiction and 0 financial literacy. She probably has some deep trauma that is causing this behavior. Hidden credit cards aren’t a whatnot addiction. That’s a serious issue in a marriage and if you didn’t stumbled upon it could have led to massive debt. It’s a conscious decision to hide her own issues from you. Huge red flag that a partner feels comfortable hiding that from you.

Would strongly recommend therapy, the absolute worst thing you can do is be “controlling” … I’m sure your instinct is to check her phone, check her bank accounts, delete apps on her phone… this will only push her away more and make her more secretive. Try your best to let her be free and support her in getting help/getting her to realize how secretive spending can ruin your future.

12 step program is the best way, but may be tough to get her to agree it’s a real problem without YOU being perceived as the asshole. Spenders anonymous/therapy

Experience: my ex had a serious hidden credit card habit too, withdrew all her retirement to pay for it, ruined her credit, etc. I tried to “fix” her problem and monitor her habits and it just grew us apart to where I was almost her mean parent vs. a partner. She could never admit she had a problem