what would i do? depends on a stupid number of other factors. for a start...im married, so do i love my wife, do i really want to have an affair? would she know? could i get away with it? would i "want" to get away with it, would the guilt be too much for me?
i think if this was me, id recall the first holiday as a good memory and leave it at that. I mean come on! 12 years later - is she THAT attractive, in all aspects? id leave it, keep as friends even, but i wouldnt take it further. thats me anyway.