You bring up points that I always wonder about when people say, "I had no idea he/she was cheating on me."

The only thing I can think of - is that they are so trusting, that they overlook the obvious and create excuses for the exceptions that do not follow a pattern. Truthfully, I know I don't know most of what it entails...but I can't help but ask - "How do they not see it?"

Maybe I'm just not being empathetic enough.