QOTD- Wedding Nightmare!

Ok, so I'm straying from my 'list' today, but I figure I can throw in some extra questions

I was trying to fall asleep last night, and had a 'wedding flash'. I can't really call it a nightmare, because I was still semi-conscious, but it was a truly frightening thought.

FBIL has been surrounded by weddings and engagements lately. First his cousin, then his brother (FH), now one of his best friends just got engaged. He has a gf that he has been with for maybe 2 1/2-3 years now, and although they're 'young' (they're both my age, 23-24), they probably will get engaged at some point in the next few years I would assume. So I think he may be getting some ideas in his head.

So my panic-inducing flash was...what if he proposes at our wedding???? Sometimes I highly question this family's thought process...like they would totally think this is an acceptable thing to do, because it's a family affair. Yes, they are that @$$ backwards sometimes.

So my question to you ladies....what would you do if someone proposed to their gf (or bf) at your wedding???? I mean, what would you REALLY do, and how would you REALLY feel. I don't want to hear someone get all Pollyanna and say it's a beautiful wondrous thing and then have everyone lemming off that. I want honest, REAL emotions and actions.

Like, would you willingly sacrifice your cake to go grab the girl and smash her head into it?

Not that I would do that, of course. I do like FBIL's gf, just I would be extremely hurt if they were do do something like that at my wedding. They have a pack mentality, and sometimes I don't think much care or attention is given to an individual's feelings. So while I probably wouldn't go smashing heads, I would probably have a VERY noticably pissed look on my face, and discretely excuse myself from the party for a few minutes to go sulk in the bridal suite.

Ok girls...be HONEST.