I can assure you that fasting while being on keto/zero carb is very different from fasting while eating a carb based diet. I also have a history of eating disorder and fasting used to lead to monumental binges and food obsessions. For this reason, I avoided it like the plague. Now that I am keto, I can fast for 48h and then eat a normal meal with absolutely no problem. This amazes me, it's like food is no longer overly rewarding to me, and I am in full control. I used to think that my disordered behavior towards food was of psychological nature, I now tend to believe it was mostly pysiological. Carbs just do something to the chemistry of my brain that makes me feel like a junkie around them. Anyways, I'm saying that because you should really not impede yourself from trying to intermittent fast/fast in the future on the basis of your previous experiences with it. Also, insulin resistance is frequent in former bulimics/binge eaters. Fasting is the most efficient way to improve insulin sensitivity. Just throwing it out there :)