This may be a little late, but a very good book that has helped me have a more positive body image is "Intuitive Eating" written by a couple of counselors that deal alot with emotional eating, body dysmorphism, etc. Here's the link http://www.intuitiveeating.org/content/what-intuitive-eating
I think the most important message the book relates is that deprivation never works, and only through truly appreciating and listening to your own body will it then follow that you will eat and exercise healthy.
p.s. In high school I was 5'0' and weighed 105 pounds - 4 inches shorter and a little heavier than the OP - and I too, thought I was "too fat". And yet, I never had difficulty finding boys who were attracted to me. DON'T BELIEVE THE PICTURES OF "MODELS" IN THE MAGAZINES! The vast majority of those women are SERIOUSLY underweight and under-muscled as well as air-brushed!