Oh come on
get a morning coat, will ya
Tuxedos are called "dinner" jackets or "evening" wear. Hint-hint. XD I'm sure your bride spends a f..ton on her dress, so why shouldn't you get something to match it? It's your wedding! (EDIT: sorry I reread your opening post and see you didn't mention it's day or evening wedding. If the sun is going to be up during the affair, I think it would be an awesome present to your wife-to-be to get proper day formal- or semiformal wear. If it's evening, just get a tux.)
Seriously, that said I think a tux is awesomely versatile, at least if you live in a city and like art and other fine things. Going to the opera, an upscale restaurant, an art exhibition dinner, or similar stuff isn't the privilege of billionaires, and present a pretty good opportunity for putting a tux to good regular use.