Not an odd question at all.....
When I have made all day fishing trips with my wife I have a porta-john (red jug) that I use that also has the female adapter. It did not overly excite my wife so most of the time she limited liquid consumption and has a bladder of steel.
I still keep that in the boat but also have a 5 gallon bucket if need be.
One thing to remember, it doesn't hurt to have a neutral colored towel or blanket with....something that doesn't draw attention to others on the water screaming...."Look at me pee!".....or at least my wife is that way.
I have had a couple of friends who had dual livewells in their boats turn one of them into a makeshift #1 only potty for their wife/kids as it is easy for them and leaving the plug out....enough water cycles in and out that it flushes right out.....unfortunately, my boat doesn't have dual livewells for this solution.