Recognize that stess can come from good events or bad events. A death in the family (I'm sorry you lost your uncle) causes stess. An exciting birthday party causes stress, too, even though you don't feel it the same way. It's still there.
When you recognize that, then do things that soothe or relax you and help you to deal with that stress. Just managing the time in your day can be a source of stress, so getting better at time management can help lessen that.
When you are better at managing stress, you're better at taking control and making good choices when it comes to food.
Exercise and more physical activity can help you deal with stress, too! Just doing something physical and allowing yourself to enjoy it, or choosing something you enjoy doing, is a stress-reliever in itself. Doesn't work as well if you use it as another source of stress (I'm bad at this activity, why can't I do more, why can't I be better...)