That' heavy. Would your friend have done that if you had a medical condition like diabetes ? I doubt it. Eating disorders are medical conditions needing special treatment actions and regular check ups, too. She should be ashamed of herself. If she wasn't a total pig I would suggest to say something to her in private, but it sounds like she has no tact at all so I wouldn't trust hem not to blab your business. She's got the typical profile of a girl who wants to be on top of things, you know like those girls who want to work a room and lead a party. Kind of a 'control freaks triks' users. I hate that.
Binge eating is just like any addiction. Though statistics say it is easier that one is a bit easier to beat but I don't believe those stats. I used to be a fairly heavy smoker. I quit three or four times but then after a while I would be in a social situation with cigarette users and say "What the hell" and take one. OMG....it tasted soooooo good. Within a month I was back smoking over a pack a day again without even trying to take anti tobacco actions pills to stop again. What did that last accident taught me ? (1) I realized that I can't have "just one"; and (2) when I did fall off the wagon, I got right back on it. I didn't beat myself up, and never promised myself that I would commit suicide if I ever had another cigarette.
Don't beat yourself up. Just get right back on that wagon, and good job so far keeping yourself under control !!!