That's interesting, Applejack. My wife an I are similar to the situation of you and your wife. I was raised in Utah, so Utah-isms are sort of second nature to me. My wife is from Arizona. She has noticed the Utah wife/mommy culture you mentioned with the blonde hair, tricked out minivans and SUVs, big houses, etc. My wife doesn't like that part of Utah, but she does love Utah -- like a lot. We moved down to AZ for a few years and it was actually she who wanted to move back up here. She sees that annoying LDS-female-suburb culture as more of just one slice of the population that you can easily avoid if you want to.
Anyway as for the study about Utah and stress, my take on it is that many Utahns lead busy lives -- but by choice (for better or worse). Sometimes we might feel compelled to in the case of church callings, but as our state emblem denotes, we are "industrious." We're busy running around raising families and having careers, involved in our kids upbringing: schools, teams, clubs, etc., and in this state we tend to have a couple more kids than the average American family. It can be stressful at times. I've seen just as many or more studies that point to Utah as a happy place; I don't think that's *all* because of anti-depressants.
There are plenty of days that if I got some anonymous poller on the phone asking me if I were stressed, I'd answer in the affirmative, and I'm not some hard-charging overachiever. In fact, my family is pretty low key. But life is busy. Raising four kids is time consuming. I get home from work and it's not rest time, it's actually go time until 9pm.