Wow, my name is Jessica too
Anyway, I know how it is. I'm tall and look older than I am, so guys tend to be intimidated by me. But, I don't think you should be jealous. I used to always be so jealous of my older sister, because she would always have boyfriend after boyfriend and guys were constantly hitting on her. But you know what? She was never happy, and the guys that were hitting on her and dating her were only after her for the way she looked, seeing as how she is one huge SNOB! She's never had a good, meaningful relationship (and I know I stress this a lot, but it's true, I believe the most important thing in a relationship is MEANING...) but rather shallow ones that don't last long and involve a lot of heart break.
Your time will come. Those guys are jerks for not liking you simply because you "aren't pretty enough." Everyone is beautiful in their own way and some day you will find that prince who will think you are the most beautiful girl in the world.
Just be patient.