After a year in which I got to be in three wedding parties the biggest thing I learned is that the hierarchy at weddings (and their rehearsals) goes:

1) Wedding Planner,
2) Brides mom,
3) Bride

I realize that seems completely backwards, but in my limited experience the bride will defer to her mother, and mom will defer to the wedding planner, if there is one (otherwise remove #1) probably because #1 is being paid to make sure things go off like #2 and #3 want, and because the fortylevendozen other things the bride has to do is why wedding planners exist. But unless #1 is a man, the sum total of men involved in the decision making process is zero: As men, our job is to go where we're told, when told, dressed as told and do what told. Not in general, let me be clear, but regarding the wedding itself. You may think it's your wedding, too, which it is, and that you have the right to voice your opinion as well, which you do--but it will probably be ignored and you do so at your peril; she's been planning this since she started walking and had all the suggestions she needed before she even met you. If you need to ask clarifying question to be certain of your responsibilities, do so ASAP, but otherwise smile, look pretty and try not to look as uncomfortably out of place as you feel. Oh, and don't let the fellas keep you out till 4AM at a strip club the night before the wedding.