meh, probably kinda both. I don't think riding now is any more badass than riding in the summer... it's just a thing I do, NBD... but the dumbass factor is probably catching up to us as it gets colder.
I commute 11 miles each way every day in Madison. It's already been -15F twice so far this year (not including wind chill, which really doesn't mean anything on bikes unless you also account for your own speed and direction), and that wasn't bad. Comfort-wise, just make sure you wear enough stuff , and maybe make some extra effort to cover your entire face just in case for frostbite. Big scary numbers aside, it's really only five degrees difference.
Safety-wise, you're pretty safe no matter the temps AS LONG AS you're dressed properly, and you're on the bike & moving. Biggest worries are falling and mechanical failures. Obviously watch out for slippery places, and if you do fall, get up and movingas soon as possible. I would ditch the tools, because if anything breaks there's very little chance you'll be able to make it through the repair without getting very cold. Better IMO to be able to call your wife or a co-worker in case of emergency, or flag down a passing car (this is why I only ride on well-traveled roads in the winter). Make sure your bike is in good working order (just working... no need to try and make it look pretty with all the salt you're riding through daily), and get some very good flat-resistant tires.
I definitely wouldn't be going out for fun rides in these temps (there's plenty of other stuff to crosstrain with besides bikes), but if it works for you, it works for you!
As far as your sock situation goes, I agree that you probably have too much compression, not only of your bloodflow, but also the socks themselves. As you cram more sock in there, you squeeze away the air pockets in the knit. That air is what provides the insulation, not the sock itself, so one or two loose and lofty socks are often better than three squished socks. Another trick is to throw a thin layer of plastic (grocery bags are good) in between your sock layers, to add some more air layer separation. Insulated boots are really the most effective way to go though.
Finally, I'm not married so I don't have to worry about this, but maybe it would be better to drive for a few days just so nobody has to worry? Like I said earlier, there is a dumbass factor there somewhere, it's just on a sliding scale and your breaking point is probably way different from your wife's