Legal protection from husband's potential debt?

Before we married, I knew my husband and his partners were planning on opening a second restaurant. When they did so however, they had to get loans from private investors (the bank wouldn't loan to them). Despite my persistant questions, my husband wouldn't tell me how much they borrowed, or when the loans would be due, or pretty much anything. He did tell me that we would personally be on the hook for the loans if the restaurant fell through, because despite being an LLC, they had to personally guarantee the loans. I kept asking for more information on the financial state of the business, and got no answers. I kept suggesting things and asking questions about the business in general, and was told it was "none of my business." Now my husband hasn't been paid for seven months, and the business is in trouble. I have been paying all the bills.

If I had been smart, I would have asked for a pre-nuptual agreement to protect myself. Now I'm married to him, but I don't want to have to take on potentially huge debt when I have not been allowed any knowledge about, or input in, my husband's business.

I don't want to divorce him yet. The financial stuff bothers me, but it's not as important as our relationship. I want to see if we can work things out. However, I still want protection from the debt I could face if his business falls through.

Is there some sort of "post nuptual" agreement, or immunity contract we could create, so that I can stay married to him but not have to pay for his debt if the business fails?