FY, In her mind, you are denying her the car after all of this time. Like a child, she's throwing a hissy fit. You don't reward this type of behavior. What I would do is allow her to calm herself down and do not have any more discussions w/her about the car until she does. At that time, you can explain that you want to ensure that the finances are in order and go from there.
If you go out and purchase the car now, she will, like a child, use this behavior again to get what she wants. Step back and give her a wide berth to diffuse that anger. Some will say that my advice isn't the best, but like you, I wouldn't reward this type of behavior.
Good luck!
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
