Or you could do "50 Shades of Gay" and have the front of your t-shirt made up like the cover of the "50 Shades of Grey" book.
Or you could put "They lived Happily Every After" on the front, and on the back a pic of you and your partner/spouse. The back could also be two stick figures, both with top hats, or both with wedding veils -- depending on if you're a gal or a gentleman.