I've been having this issue with eating too many Skinny Cow treats. So, every time I want to eat one, I ask myself, "Would I eat an omelet instead?" If I am willing to make an egg white omelet, I know I am actually hungry. If I just want the treat, I eat if I haven't eaten one yet--or I say no if I have.
Sugar cravings are often brought on by protein deficiency, so if an omelet sounds equally appealing--I know it's that--not emotional hunger.