Eh, we just don't talk about it.

My fiance works in a t-shirt printing shop and I work as a developer. I enjoy hearing about his work, he enjoys hearing about mine but we know neither of us could do what the other does.

If the occupations are so alien to each other probably you wouldn't be attracted by that person to start with. If your SO is eg. an hairdresser probably it is boring but if her occupation is something you would like to know more about, it's not. As an anecdote, my ex was making a thesis in International Relations and at the same time she was taking a Spanish Philology course. I can say to you that I learnt a LOT just by being nearby.

Probably what you like is that she is smart enough to understand what you say. That doesn't imply that she has to be a scientist.

> nothing really important at stake

Speak for yourself..