when I was house shopping, i ran across a website that would pull FBI and other local gov't stats for your zip code. it was very enlightening. It was interesting to me to see that just moving 5 miles away, the crime rates were halfed! Also, it was very surprising to see that the area I'm currently living in has a pretty high violent crime rate, ie Murders, rapes, muggings. Plus, some of the other stats were neat to see, like tax rates, income levels, ethic demographics, etc.
You may try just going to the FBI site...I believe the link I followed was off one of the real estate sites.
Does your wife allow loaded guns in the house for home defense? As in the gun in the nightstand, shotgun behind the bedroom door? If she agrees to that, then it doesn't make sense why she would be resistant to taking a gun along on errands. You may be able to work that angle. The odds of someone breaking into your house at night while you're there (living in the country) are probably slimmer than being mugged while in town!!
But the point is, crime will hit anyone at anytime at anywhere, best to be prepared.
Good Luck!