A few things that worked for me.
1. Twizzlers. At work, I realized that I liked the break that I had to take to go outside to smoke. So, I just took a red licorice Twizzler, went out to the deck and ate my Twizzler. It gave me the same mental break from work, the Twizzler satisfied that oral fixation, and it was a measured serving.
2. Other finger-foods. Baby carrot sticks, sunflower/pumkin seed in the shell and MiniWheats cereal, all helped when sitting at home watching tv.
3. Avoiding triggers. I had to avoid bars, because I couldn't seperate sitting at a bar with a cocktail with smoking a cigarette. I actually still have a problem with that, 10 years after quitting.

Wish her luck, and just bear with her. The mood swings can be pretty wacky.