When I feel that way, usually there's something else bothering me emotionally that I'm trying to 'cover up' with food. It's difficult, because sometimes I don't even realize that's what I'm doing until after the binge!
One thing that might help you discover why you do it, is to write down what you're thinking and feeling as you eat. Try to do this in a non-judgmental way, so that you're observing yourself, rather than being hard on yourself. This might help you take a first step towards understanding why you want to binge. One thing that helps me is to 'eat mindfully,' meaning that if I feel like binging, I sit at the table and eat my meal without watching TV or going online, and try to be present with the fact that I'm nourishing my body. Usually this reduces the amount I eat, so it's a good start anyway!
When I had a stressful office job, I used to snack constantly, because I always felt like I was hungry. After 6 months or so of this, I realized that I was snacking because I was nervous! So I eased up on the caffeine, and brought only healthy snacks so that there was less temptation (and guilt) when I had to satisfy my oral fixation. Then I also felt less guilty when I did eat junk food.
It can be confusing to be binging and not know why, but have faith that you'll figure it out

You're already halfway there by realizing you're doing it, and that you want it to change. Good luck
