@jcboy,
Well, I used to know jewish people who would never ever ever buy a german car, but also some who have bought mercedes and bmws for what I take as personal reasons such as "I'll show you". I'm not jewish so I can't speak for individual jews or anyone else but I shied away from things german for years, possibly typical for people my age and place, but I'm decades over it, from reading about and knowing germans. I don't mean I shied away from things nazi, I mean anything german. That's part of a long life, sometimes, that you change your mind.
Maybe your father was somewhere on that continuum.
This is also part of how I can see people in other places strongly resenting or hating u.s. americans, that I held resentment to another place myself. But I know we aren't all pond scum, and neither were they.