How common would it have been for a man who traveled a lot for work to secretly have 2 families in the late 70s early 80s?

Listen to her, and never bring the subject up again, or your are DEAD. Do as she tells you to do, and NOTHING MORE. Poor thing, you did exactly the right thing under the circumstances.

Not your fault, even if she blames YOU, accept it,apologist, and hope she accepts it in the long run.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.