You cannot assume anyone on the road is sane.

 

Some of them are on drugs, soft or hard.  Some of them are looking for trouble to alleviate their pent-up anger. If you happen to cross their path, bad thing can happen.

Be always courteous and considerate, for the safety of your own and others. Turn your head.

Rain or shine, turn the visor to your left (if that thing is designed correctly.)  It blocks the UV to the left side of your face. Over the decades, it makes a difference.  When they cannot see your face, they are less likely to confront you.

You did the right thing by keeping your cool and did not engage. People do things because who they are, not because who you are. Her behavior said nothing about you, but plenty about her.  She would not want her boss or coworker to witness the scene.