I've struggled with purging for a little over a year now. I don't tend to binge eat so I don't think it's bulimia but it's definitely a problem. I'd managed to stop for a while but I lapsed recently. Hopefully it was just a lapse and not a relapse, I can't face going down that path again long term. I've burst blood vessels in my eyes and give myself nosebleeds from vomiting so violently in the past. A friend of my cousin's even asked him if I'd been purging because she recognised that my cheeks were puffy (she is a recovering anorexic and was hospitalised for it, so she knows a thing or two about EDs).
Thing is, I identify with a lot of what you say, the sense of release and reward is so immense. Feeling hungry is a buzz, feeling full feels disgusting. And the act itself feels cleansing. But yeah, the comedown of shame and the addictive nature of it definitely gets you in the end.
My way of dealing with it has been by trying to eat healthily (fresh fruit and veg, lean meats, complex carbs, low fat) combined with exercise (NOT over exercise). For me, as a guy, it's more about being toned rather than really thin, so I've been weight lifting too. And doing this I realised several things - firstly, this is REAL control. Purging feels like control, but it's not. Simply adopting a healthy lifestyle, once you can manage to do it, is proper control. If you're destroying yourself and you can't stop it, you're out of control. Secondly, purging all the time results in becoming undernourished, and without getting the right vitamins and minerals it will only make your depression worse, which will make you even more self-loathing and self-destructive. It's a horrible viscious cycle to be stuck in, and obviously both of us have learnt that the hard way. Moderate exercise and healthy eating will result in natural healthy weight loss - purging, starvation and over exercise will fuck up your system and bite you in the arse. Over the past 2 years I've lost about 65lbs - half of that was before I started purging, and a further 15 was after I managed to stop, and started regular cardio and weightlifting and healthy eating. The buzz I got from losing a whole stone in a natural healthy way was far superior to what I felt from losing weight by purging.
I know I know, I'm lecturing and you probably already know all this, in theory at least. But I figure, if you hear it from someone else it might make it a little harder to ignore. Do you have a doctor you can talk to about it? In any case, we both know that purging isn't the answer. Take care.
I know someday you'll have a beautiful life, I know you'll be the star in somebody else's sky...
But why can't it be mine?