Just to add to what Mithalwen has posted, Green is a colour rarely worn (in RL), as it is seen as unlucky. There is a superstition that if the Bride wears green then the faeries will take her away. From a similar origin comes veil wearing, as it was seen to be important to 'protect' a bride lest the faeries see her face and steal her; bridesmaids were also said to be used as further protection, in an effort to 'confuse' tricksy sprites by being confronted with a whole bevy of lasses.
I'm not going to say much about those Elves who 'married' by 'doing the deed', but it does conjour up some strange mood dampening images if they made sure to say their 'blessings' before um...getting down to it.
