Tips on getting through exam stress without ED crap?

Um. So I keep messing up.
I went ages without purging and now I keep doing it.
I hate myself for it.
I'm letting Jenna down and not doing enough revision.
I know it's because I'm stressed.
But like, a bit ago, I don't even know what happened. I don't remember eating but all of a sudden I had purged and I don't know why. I had eaten but not consciously.
I'd just come back from the shop - but a good thing was I didn't buy any binge food!

I don't want to do this.
I don't want to keep letting my girlfriend down and making her worry and making her work and exam life more difficult.

I'm such a terrible person.
Please, if you have any tips on how I can focus on revision and not keep doing stupid selfish shit like this, let me know?

Right now I want to die because I feel so guilt and filled with self hate. I want to cut and burn and OD and make it all stop.

I saw "tips" and was like ZOMG tip-sharing

First-off, you're not letting me down twinkle toes.
And you did really well today; you stayed safe for like six hours on your own before you had a little kerfuffle. Yes, today wasn't perfect, but it was a pretty damn good effort! Maybe applaud yourself for today's successes and then spend this evening focussing on your revision, then we can tackle tomorrow when it comes.

I haven't given much advice here, many apologies! I just want you to know that you're doing so well <3