Have you sought any legal advice? Have you taken steps to protect your finances?
She is already charging things without telling you. If you don't take drastic measures, she will destroy you financially. You cannot trust her. This woman is not the girl you married.
You need to get your money in a private account, where she can't touch it. You will be paying for the trip to Mexico, plus much more, if you don't take action. Call your CC companies and shut down the credit that has both names, or take your name off the card......or whatever it takes to prevent her from using your credit.
Look, I understand that you love her and want to save your M. I get it. Right now, however, you have to save yourself! Many a man has been financially ruined by thinking his W will wake up, or by trusting her to do the right thing toward him. She is looking out for one person.......and one person only.......herself.
You can even see your action as helping to save the M from her. She is out to destroy it, so do what is necessary to protect your property from her. If she comes back to the MR, she will be glad you did.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!