A few weeks ago in Vietnam we met three British women in their 40s-50s cycling from the UK to Australia. Sitting around the table at the cafe were four cycle touring women (including Amanda, my wife) and me, so the conversation naturally turned to the difference in touring "styles" between men and women. Here is an outline of the conversation... from my male perspective.
-Touring is not a race. Whoever is less fit on a particular day (she will surprise you) sets the pace.
-The group found it helpful to set small goals (every ten kilometers rest a few minutes and drink water)
-The toilet/pee spot issue is very different for women. Start looking for a suitable spot to stop before it is becomes pressing.
-Eating. Every touring couple we've met has commented on how the female bonks sooner than the man when they have not eaten. Physiologically, I do not know why this is. Always have a few snacks handy and do not push beyond the feeling of lightheadedness. That goes for both of you.
-Route Planning: Amanda does most of the research and planning of routes. She is more detail oriented than I and she can determine how far we go on a particular day. We are both happy with this.
-I respectfully disagree somewhat with the light-load-short-days-she-decides-everything rules above. If you are a good couple you will be able to find a middle ground where you are both enjoying the trip.
Happy travels