I am not specifically familiar with Florida real estate law, but I do know the laws for Utah and for Arizona.
In those states, the lease would be enforceable against anyone who has signed it. The idea called "Statute of Frauds" says that a real estate (rental) contract has to be in writing in order to be enforceable. So if your wife never signed it, then she's got nothing to worry about.
As far as you performing your obligations under the lease, that's a gray area for three reasons: (1) a contract has to have something of value exchanged in order to be considered valid. If you didn't give any money to the landlord yet, then technically the contract is kind of in limbo still.
(2) Depending on the level of douchebaggery you are willing to entertain, you could also just walk away from it. But that's kind of an a-hole thing to do if you feel like you have made a promise to someone.
and (3) If you do walk away from the lease, then you're looking at gambling on whether the landlord will actually pursue you (and the other couple?) for performing your contractual obligations. I have sometimes gone both ways on this in my rental properties... I know I have intentionally sued someone even though it would cost more than I would receive just because they were a jerk. At other times, I have decided not to sue... especially when I knew the situation.
My main piece of advice would be that the contract may still be in limbo, and that rather than asking the internet, you might talk with your landlord and explain the situation to see what can be done.