Upon discovery, I’d be hurt, my trust would be broken and I’d become suspicious how much of our relationship was fiction.
Would I leave? That would depend on his answers of why and what he did with the money. I’m gambling anyone who would do this doesn’t respect, trust or love their spouse.
If it’s a bf, it’s their money and I don’t need to have a say unless we’re living together, splitting expenses and for some reason he’s been having me pay the greater amount under the guise of not making enough money. I’d leave if that was the case.