Something to keep in mind is that most of the heroes in 9/11, who were at the site, are dead by now or on their way there with a whole host of medical complications. There was basically no way to avoid the smoke/dust that came from it, and everyone in the area was effected. All the ones that I know from it have PTSD as well, with a couple of first responders being forced by their PTSD into early retirement.Sounds like things most likely worked out for the best. Would never have meant your wife in NYC and could have possibly been killed or injured on 9/11.
But you never know. You could have been in the towers on 9/11 and become a hero helping people get out of the building. Then got married to a great woman in NYC once you became known as a awesome and heroic guy.(not that your current wife isn't awesome im sure).
A whole lot of life is out of our control and we are influenced a great deal by chance and circumstances