Am I the only one who thinks a big wedding is inappropriate for two people who have been living together? I think it would be tasteful to have the wedding performed privately, down at City Hall some day, and then announce the news in an invitation to a big party that occurs on another day and that specifies no gifts. There is no new household being set up, and you should be glad people want to take the time and make the effort to attend a party celebrating an existing relationship.
It seems to me that the idea of a big wedding ought to be about the beginning of the couple's life together. In fact, the really cool thing about a wedding back in the old days or for traditionalists these days is that the couple has not yet consummated the relationship. When that is the situation, there is an excitement and the reception takes on a wonderful glow: look, they're finally able to have sex and yet they are hanging out, dancing here with us! If this is not the case, how can the couple imagine they're putting on a show that justifies everyone watching and celebrating them for hours?
UPDATE: Interesting comments section! Let me just quote something I wrote, somewhere down in the thread:
Do I seem like a "social con"? I guess I've got my own distinct mix. I'd say I respect the genuine traditionalists, that I don't seek a traditionalist life for myself, and I tend to scoff at the fence-straddlers. People who live together and then want a big traditional wedding are very conspicuous fence straddlers. Be something! Stand for something! Think! That's my message.