O'Hara,

Read your "shame and debasement" post and was stunned that you have
failed to train a crew. If you fell overboard everyone might die. I bet your
wife can cook, drive a car, etc. so why can't she sail? Clearly she is
capable of learning stuff.
Rather than trying to analyze and correct your teaching skills send your
wife to a school run by someone with a reputation for competence. The goal
is for her to learn how to sail not for you to learn how to teach.
I'm assuming here that your wife does want to learn how to sail.

Dave M.