Getting an anniversary present can be difficult, especially if you don't know your spouse that well. Any of these tried and true suggestions are guaranteed to make them swoon:
Get them a new car—with a giant red bow on it: A new car is an exciting gift, but without a giant red bow to demarcate it as such, your spouse will simply assume the car is on your property so that its true owner may rob you.
Get them a dream vacation: Make sure it's the vacation of their literal dreams, such as a trip back to their old high school wearing nothing but their underwear, or an exact replica of their current house but with unsettling key differences and mysterious doors that lead to nowhere.
Give them what they really want: Freedom from the burden of being in a relationship. They might be sentimental about breaking it off, so to truly bless your sweetheart with 100% freedom, fake your own death by dropping a mannequin full of blood pudding into the mouth of a whale shark.