I would start going to family therapy w/o the wife.. set an example...
Get a biz card from teh FT and pass it to the wife iwth a personal note from teh FT on it inviting her to join in...
Keep in touch with all of her friends... tell them you and she are having trouble, and ask for their HELP in supporting your marriage and DISCOURAGING her straying.
This is a political campaign... time to roll up your sleeves
