How to convince my mistress to stay?

Anonymous
I'm in a dead marriage that can't end for business reasons. I have a mistress whom I love dearly, and have been seeing for just over seven years, with my wife's tacit consent. I support her financially to the same degree that I do my wife. I pay for her apartment, her car, her groceries, her medical bills, and provide a credit card with a reasonable monthly limit. I have life insurance policies with her as beneficiary. I spend most of my non-work time with her, day and night. However she is insisting it's not enough. She wants to be married. She understands the reasons my marriage can't end, but she says she doesn't care. She would rather be destitute and married to me than financially secure and comfortably kept, and says I must marry her or she'll leave me. I love her dearly, but my life would literally become a financial disaster over night if my marriage ended. How can I convince her not to destroy a good thing?
How to convince my mistress to stay?
5 Opinion