Hops fade over time, as people have said. I'd add more hops than you might normally (but I like hops!).
I would also store them (or at least a 6 pack a time) in the fridge. The yeast will drop out and the beer will be clearer.
In any event, if she drinks just one beer a week, the ~24 bottles will be gone in 3 months. That is not too long of a time. I have kept GF beer (porter and English pale ale) for 6+ months and they have gotten better over time.