Question: What can I do to avoid eating more when I'm sad/stressed/anxious?
Answer: It's very common for people to eat in response to feelings. In some cases, even positive feelings will provoke eating. It's just throwing people off their regular kilter which will sometimes do this. But what's more common, of course, are negative feelings: loneliness, anger, depression, anxiety, whatever it happens to be.
Now, it's not unreasonable for people to expect to do something to comfort themselves when they feel bad, but of course it's a problem when the comfort becomes something that can do somebody harm, like food or alcohol or tobacco or drugs.
So the trick to solving this problem is to find some nonfood way of bringing comfort to oneself, and to respond to these feelings in a more constructive way than eating.
A perfect example of this would be to do relaxation techniques, to do yoga, to exercise, of course, would make the most sense, to call a friend, to watch a show you like on TV, to read a book. There's a very long list of such things that make people feel better, the issue is what's going to work for you, and what can you use to comfort yourself, in lieu of food, when you're having unpleasant feelings.