Not bulimia but I had re-occurring OCD throughout my teens. It would flare up whenever I was very stressed. Often as a result of bullying. I suppose as some sort of messed up control mechanism. It came with the whole constantly washing my hands thing...part of me feels like that part was me punishing myself. Like when you feel worthless and you think you deserve to be trapped and miserable.
When I finished school it lessend significantly and when I moved away from home, it vanished :)
I know buliemia might have the element of wanting to lose weight/body dysmorphia to it. But I think for me my ocd boiled down to being a coping method and also, my lack of self worth and I could see how bulimia might have the same causes for you...?
Anyway, for me it took a total change of lifestyle. Not that that would necessarily work for you, or that it is that simple to change our lives :/ but if there are specific things triggering your buliemia, maybe try to pinpoint them and if possible remove them from your life.
The working on yourself part and out self esteem ect...that's the harder part I think :) but you can do it, im sure, I just wouldn't like to think that you think it's 'all you' because it might not be. It might be that some things around you need to change and you need to make those changes.
I hope you have someone decent to talk about things with, sometimes although they can't change things, it's just good to have that person to talk to. I wish I had shared what I was going through with others rather than kept it to myself. Being alone dealing with mental health issues sucks!