I have managed to beg off every wedding in the last year. (We separated a year ago, divorce is draggging out.) Everyone has completely understood. Even though one was my directors... and I knew it would be an awesome party, well, someone had to work, so I volunteered.
Even though I think I'm pretty strong, and in a pretty good place right now, I probably wouldn't put myself out there and go to a wedding even at this point. It still stings too much.