Interesting.
There was no way that Michael was going to tell Kay the truth about what he had done and what he had become. He didn't want to lie to her or hurt her but she sort of forced the issue.
In the novel Michael speaks of the relationship between his parents and tells Kay something along the lines of (paraphrasing) "Maybe after you've been married to me for thirty years, I'll tell you some things you really don't want to hear anyway".
The women in the family know more than they let on. Kay just hadn't been around long enough at that time to know how to read between the lines. The character was also incredibly naive.
"When the snows fall and the white winds blow, the lone wolf dies but the pack survives."
Winter is Coming
Now this is the Law of the Jungle—as old and as true as the sky; And the wolf that shall keep it may prosper, but the wolf that shall break it must die.
As the creeper that girdles the tree-trunk, the Law runneth forward and back; For the strength of the Pack is the Wolf, and the strength of the Wolf is the Pack.
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