I own it, I accept the consequences. I probably could have handled it better, yes. In fact, none of this detracts, nor aligns with my goals. So when you frame it in terms of goals, it wasn't necessary. Saying nothing, and keeping the card would have sufficed.
So TT I think you did what your true self wanted to do with the card. What you didn't like is the response you got from it. If she never found it would you be ok with your actions? If she didn't react the way she did would you be ok with your actions?
I can't stress this enough. Everything you do moving forward is what is in the best interest for you and your kids. How she reacts to anything should have zero effect on you.