Me too - emotional eating is my biggest downfall too. I've been low carbing and find that helps as you can still have some treats, just not carby ones - I have a few nuts or some posh cheese etc. It has helped even out my food cravings too and I want chocolate etc less. I do find though, that if I decide to allow myself something carby as a treat, I then find it very hard to stop. And fundamentally I should probably try and get out of the food as treat/reward mentality.
Paul McKenna's book and Susie Orbach On Eating both address emotional eating. To save you the time and money, these are the two 'thoughts' that I've taken away from them that help me a bit.
From PMcK - if you want to eat because you're miserable, you are hungry for something but it's not food. Food will not fill the gap, so there's no point eating because however much you eat, it will not be enough. Do something else to soothe yourself instead (bath, walk, chat - you know the kind of thing)
From Susie Orbach - remind yourself if you're bingeing (or just eating too much of something that you don't need) that you are going to have to stop at some point and whenever you stop it will feel horrible, so you might as well stop now and get it over with.
Don't feel bad, it's very, very common and in my opinion probably one of the main reasons so many of us are bigger than we should be.