You just present yourself as a mature, calm, responsbile adult... SHE will look like a child in comparison... DO things that look adultlike... talk to friends face to face... none of this ridiculous texting crap...
Sit down, talk like a responsible parent, etc.. Tell everyone despite HER destructive choices you love her and want to save your amrriage and ask for their support... dont' say anything mean or horrible about yoru wife at all... They will see THAT and HER story and they will know who's lying to them...
This is much like a political campgain rife with character debate.. you want to win this...
Keep your head high, try to remain as respectable as you can in comparison to her sneaking around trying to smear you... most educated mature adults will support you over her tactics.. those who don't... well, this is the time where you find out who your friends are...