Kay was the one that was the anomaly. Mike was way up in New Hampshire, in Dartmouth. It was cold and dreary and Mike had just come back from war. Now he was away from his family, his food and his women . In his lonliness he falls in love with a college girl who just HAPPENS to be a W.A.S.P., another act of rebellion against his father's traditions. Tony D said

Sicily has been influenced by Arabic culture and was in fact ruled by the Moors about 1000 years ago. Much of Sicily's modern culture retains those influences. All cultures are a mish-mash of other cultures that influenced them. For Sicily this included traditions of the Roman Empire, Greek influences, North African Moorish influences, as well as feudal and Norman influence.

This is very important. Kay was not just a different culture, she was a different race. Subtle, but different. Mike didn't slap her when she admitted the abortion, he slapped her when she spoke with contempt about "...this Sicilian thing!"
Apollonia may not have been a better wife (I believe she would have) but she would have understood the life. She was beautiful, and charming and I was hit with the THUNDERBOLT 19 years ago and my wife and I are still together.
I am not being sacreligious, but the Bible says " be not unequally yolked with an unbeliever" and metaphorically speaking, it applies here.

Sorry for the rant, " someone struck a noive".