I think you just have to try harder with your wife and refer to the "infatuation" thread (
http://www.tfproject.org/tfp/showthr...threadid=26225).
Instead of permitting yourself to think about this girl as a potential hook-up (your thoughts are chosen, here), spend time with your wife. Rediscover those things that infatuated you when you first met her. Go on a trip together. Do something exciting.
Good luck, and be sure to let us know how it goes.