I have no experience in this area, so if my advice seems stupid please feel free to ignore it
You've said you eat because your depressed, it seems like your stuck in a negative habit.
It takes just 30 days to make or break a habit. If you wanted to break this habit, you could simply start on monday, and if you become depressed between then and Christmas, rather than eating drink water, do press-ups or find and kiss your wife passionately (kissing burns 9 calories a minute)
This should hopefully break the negative habit and reinforce it with a more positive one to help you with your problem, if you find yourself over-eating, do try and make it healthier rather than junk foods
Hope this helps, and Good Luck
W