How much you find yourself worrying about wetting a diaper is directly related to how well you can trust your diaper to not leak, and for how long.
Back when I used diapers like depends (the old green ones), through the more modern diapers like Abena (before they were cheapened up), I too would spend way too much time worrying about them. However, ever since I started to use premium diapers I noticed I don't think or worry about leaks anywhere near as much.
My work didn't change, but at first I did have way too many minor leaks and close calls. I also had to change while at work at least once, sometimes twice. I also had to make small changes to my life like always carrying spares and a change of pants with me.
Now though, I use only the best diapers available to me. I seldom ever think about my diaper during the day, let alone if it might leak. I keep just one spare diaper on hand, though seldom ever need it since I can go well over 12 hours before needing a change. My advice to both you and your wife is to get better diapers. They work better, last longer, are more trusworthy, cost less overall, and will put your minds to rest.