Sound like you were starving yourself, Tessa. I'd say that you should just use common sense. Eat when you're hungry, stop eating when you're full, eat good food, and exercise. I've always had low self-esteem and as a result I would always get cut and cut my scabs, leaving at least 300 scars on my body. Honestly, losing weight did help for me, so I wouldn't give up on such a good goal that can improve your appearance, health, and self-esteem.
Believe me, you are your own worst critic.