Hey Kim - I gotta believe this particular FX is a lemon, man! It happens. Call Infiniti customer relations and explain the whole situation. I would seriously be pushing for a replacement car at no cost to yourself. Go over each event in order, and tell them you have all the reciepts. Have there been any insurance claims?
Most people never take advantage of the services we already have in our existing policies, or even Infiniti corporate policies. That's why it's important to go to customer relations - get to corporate Inifiniti, not the dealerships. Having problem after problem like this is a manufacturer's defect. If it was not, then all FXs would have the same problems. Infiniti has policies about manufacturer's defects beyond warranty. It's liability if they didn't. Sometimes you gotta be the sqeaky wheel - push yourself up the corporate chain until you hit a wall. Make it part of your daily/weekly routine until they are tired of getting your calls. I honestly believe they should put you in a brand new 09 at no cost to you. That's aiming high, for sure - but getting something less than a new car might be a compromise you are willing to take, depending on what it is.
I'm sorry you've had this experience with ANY car, let alone the FX. Hope they take care of you.