I don't know if the OP was a man or woman, but if her husband was in the car it would have been his duty to kick your ass(if you were a man). This is a man law.

I can't imagine being spat on and NOT kicking the spitter's ass. You just DON'T spit on people.

It is inexcusable and if I were you I would try to apologise to that woman if I ever saw her again.