I probably will - I've been in the workforce for 15 years at this point and she is not only ~5 years younger but spent over a decade in school. Two years out of her masters, and just one year into her current full-time position, she's just hitting her stride and truly loves her job. I like mine just fine but I've been here too long, and I'll probably quit before she's ready to even reduce hours.
Since we maintain almost entirely separate finances, it's unlikely to be a problem, as I'll still do reserve duty and some casual self-employment and will bring home about what she does in addition to handling most of the housework - our sense has always been that the only thing we owe each other is equal effort and good faith, which we've always maintained quite well regardless of work hours or income.
I do lean toward a higher safety margin in my calculations, because I'd hate to have to ask her for $$.