While I applaud your thinking re your wife's training, I have the opinion that if you're going to purchase a firearm you should become a little more than familiar with it's operation and safe handling.
Please, at the very least, purchase "snap caps" or "dummy rounds" so that you may also practice loading and unloading your handgun, and become proficient in it's safe operation. Only then should it be considered a paperweight. Even then! it should be safely handled and used at a target range from time to time to maintain proficiency in it's use and safe handling.
I understand, too, the differing priorities for our free time but if you've chosen to invest in a firearm for your personal safety and home protection, treat it with the respect it warrants. When away from home and not carrying it on your person, it should be locked away out of view. Welcome to The High Road.