Since I'm not familiar with kg vs pounds and I'm certainly not a math whiz, I did a quick search to make the conversion of kg to pounds (thank you for converting m. to f - that saved me another search.. lol). Anyway, my search that told me that you went from 118.8 pounds (54 kg) to 151.8 pounds (69 kg).
Another search brought up a height/weight chart and I find the following:
Height Small Frame Medium Frame Large Frame
5'9" 129-142 139-153 149-170
Wow - what a job THAT was. lol
Now, to the practical stuff. You are NOT over weight. At 5'9" and 118 pounds, you were significantly underweight for ANY size frame. Even if you have a large frame, you are pretty close to where you should be.
I know it might be hard but you need to eat several small meals every day. Make sure you get plenty of protein and fiber each time you eat. This will help fill you up so maybe you won't binge.
You also don't mention if you exercise. A moderate exercise program is necessary to maintain weight AND it helps energize you and keeps you in a better frame of mind.