Hi Wolfie, welcome to 3FC
Studies have shown that those who skip breakfast are more likely to be overweight, now or later. Those that eat breakfast are more successful in losing the weight and keeping it off. So the first thing I would suggest is that she concentrate a little more on breakfast
It doesn't have to be elaborate, a bowl of oatmeal or even a sandwich will work. Lunches could be frozen dinners such as Lean Cuisine, or she could pack a sandwich and salad in a cooler. Suggest that she grab her cooler and go outside to eat (if possible, even to her car) and give herself a nice little break.
It's very possible that she doesn't need to follow a specific plan, though Weight Watchers is highly recommended and easy to stick to. They would guide you through the whole process and provide sample menus and recipes to follow.
Perhaps by eating a better breakfast, packing a healthier lunch and snacks, and cooking a good, balanced meal for dinner, that may be all she needs.
Exercise is half of the process, though, so maybe the two of you could take walks in the evening, or join a gym together. Or, buy a treadmill for use at home.
It's great that you are being supportive! You'd be surprised how many women deal with husbands or boyfriends that aren't any help at all. Support is a very big part of the weight loss process - and maintenance! I'm sure others will share some advice, and we hope you'll feel free to ask any questions.
Good luck!