The fact that Jews were confined to ghettos in many places means that the Christians and secular authorities knew where they were. My understanding is that they were literally, in many places, locked behind gates after dark. This would have made annihilation even more simple a thing to do.
My understanding, correct me if I am wrong, is that Jews are prohibited from marrying outside the religion. Max I. Dimont wrote, with obvious pride, that the Jews were the first people in history to prohibit intermarriage, a fact which led to a certain amount of irritation among the non-Jews, as well as a source of constant problems among the Jews themselves because of disobedience to the prohibition.
Other than your reference to intermarriage (which is valid both from a Jewish and from a Catholic point of view) you, with all due respect, are under a total misconception concerning Jews and Christians in Europe and their societal relations or more accurately lack of social interaction. Your reference to ghettoes should have given you an inkling. There was no intermarriage period as it was both illegal and invalid.
Personally, from a non-academic point of view, I don’t see any other possible explanation.
For me, and I’m sure for most orthodox Christians in the modern day, there is no dichotomy between Jews and Christians. Catholics don’t fail to see our religious roots in Judaism, and we love those things. I’ve never been able to understand a point of view that has some sort of distinction between Judaism and Christianity. Max I. Dimont, an enthusiastic Jew, says that the ultimate goal of Judaism is a universal brotherhood of mankind, a goal which is in complete accord with that of Christianity, which seeks to bring all people to a saving knowledge of the One God, the Ancient of Days, who called Abraham and promised that all people would be blessed through his descendents, the Jews.
Am I forgiven, then?