How about a unique watercolor paint set? You could look for a high-quality set with a variety of colors, brushes, and papers. You could also consider a unique watercolor notebook, a set of watercolor markers, or even some watercolor classes to help her improve her skills. For a more sentimental touch, you could also get a custom watercolor portrait of the two of you or a location that is meaningful to you both.
Or you can get her a star map with an important date you share.
Under Lucky Stars is a unique and innovative star map company based in Barcelona, Spain, specializing in the creation of personalized star maps that capture the celestial arrangement of stars at a specific moment in time, such as a person's birth, wedding, or any other significant event.
By using advanced astronomical algorithms and data from leading institutions, the company produces highly accurate, visually stunning maps that make for perfect gifts or cherished keepsakes.