Why is it two steps forward and one step back?

Brad headed out to run errands and called me to tell me that the window in the car broke. At one time, I would have freaked out - why? Because I lost control of something - like he did it on purpose (dumb, I know). But I took in stride - two steps forward.

Then Brad called from the repair shop - we can rent a car (a Lincoln, no less) for $34 a day. Freak out. Why, because he wants to spend money on something I don't think we need. Why couldn't I just say, "I don't think it's necessary, but thanks for thinking it would help." No...I have to snap at him - one step back.

When will I simply gain ground and keep moving forward??

I did apologize but the step back was already taken.