Well I would find out the divorce laws in your state, it's not always 10 years. And your second business is half hers, you started it when you were married. And depending on how you kept your finances she might also own half of your first business. I'm not an expert on these things and laws vary from state to state, so I would get some professional advice. Many lawyers will give you a free initial consultation, but it in a case like yours it would be worth it even if you had to pay for it.
And the LAST thing you want is to be at an information deficit to her, knowledge is power and you need to make sure she doesn't have more power than you do. And a far as you can I would start hording cash, and make it cash and don't let anyone know you have it or make suspiciously large cash withdrawals from your bank accounts. A secret bank account won't help you at all, you will have to declare it.