Don't be afraid to get creative; consider side tables or end tables as options. A Moroccan pouf or cube ottoman with a tray on top also are alternatives to traditional nightstands. Finally, keep in mind your mattress height; you'll want to make sure your table isn't too high or low.
When choosing nightstands, be mindful of the space available. Smaller spaces may not be able to handle more than one bedside table. Mix it up, if you are so inclined; the matching nightstand rule was made to be broken.
The bedroom; one of the most sacred rooms of the house and one of the rooms where we spend the most time (even if it's to merely sleep). It can also be one of the few room where you can design and decorate it to meet your particular tastes, and not have to worry what Tom, Dick and Harry thinks, as they'll never see it. For couples, there needs to be a balance, a juggling act, sacrificing personal extremes and coming to an agreement on a design that works for both.