"After all 43,000 motorist die each year and only 700 cyclists."
Let's assume this figure is accurate. At least half of the "cyclists" are children. That would mean 350 cyclist deaths are adults. Serious cyclists spend far more time and distance riding than than children, so presumably we have far more exposure to the dangers of biking.
Following the rules of the road, taking a lane, using lights to be visible at night all reduce your chance of collision. There is no doubt that if these factors were taken into account in the death statistics, and removed from the total, that 350 would be greatly reduced.
I am not worried for my safety when I am cycling. I have logged 4000 mi so far this year in the greater Dallas area- in spandex shorts!
Don't be too hard on your wife- It's her job to worry!

Tailwinds! ChipSeal