I'm so embarred about the size of my chest area?

Before you say anything, my mother is big in that area, my grandmother is and so is my grandmother on my fathers size. So why am I so flat? I am so uncomfortable with the way I look that I refuse to go out with friends or anything. They have what I don't and it really just gets to me. I'm not considering implants because I don't have the money. I just want a certain food I can intake all the time and have them perky up a bit. Please please don't tell me that I should love myself the way I am. I know I should but how can I when I'm so insecure about the way I look. So please, pleaseee, give me some food ideas or something. I'm 18 years old going on 19 and I'm underweight. It could be the reason...maybe I don't have enough estrogen.