I totally know about the "happy binge." I just really love to eat, and whether I'm feeling bummed out or celebrating something awesome, I always tend to think of it as "extenuating circumstances" that give me permission to put my diet on hold. Of course there's nothing wrong with treating yourself every now and then when something special happens, it's just important that you make sure it doesn't get out of hand. Pretty soon what started at "I got a promotio n!" turns into "It's Saturday!" or "My favorite TV show is on!"
This post on iVillage.com tells a sweet story about a girl who had a great day followed by a "happy binge," and how talking with her friend helped her feel better about the whole thing and less likely to binge again over emotions, good or bad.
I don't think any amount of talking can prevent all "potato chip attacks," but I bet it can help stop a few.