Well, I also eat to deal with stress (especially chocolates), but another thing that really de-stresses me is SHOPPING!
I know it's almost as bad as eating (worse if you're counting the money), but a trip to the mall will perk me up when I'm stressed out, even if I don't buy anything. I love shopping, especially when I'm not looking for something in particular. It turns out that if I'm looking for some particular clothes item, I will get frustrated and depressed because I can't find one that looks good or fits right. But if I just go shopping to "look around" I will inevitably find something I like that fits! I also shop for bath and beauty products a lot to lift my spirits.
Of course that doesn't work for everyone, especially if you don't have time for it. My advice for eating better while you're on a tight schedule is to pick healthier fast food. If you have to get fast food, go for Boston Market or Subway instead of McD's or Burger King. Also, I don't know if you have a Whole Foods Market in your area, but they have healthy premade meals and such that you can buy (most supermarkets have sandwiches). I eat Lean Cuisine a lot, which takes five minutes in the microwave and is pretty healthy.
When I used to be under a lot of stress (haha, grad school is waaay less stressful than undergrad!) my biggest problem was that I would be so tense and worried that every moment I spent not working I felt awful, and I couldn't sleep at all. I found that taking an hour before bed to do something relaxing, even if it's just watching a favorite TV show or reading a book, helped me a whole lot.
Anyway, hope that helps!