Adolescence can be difficult. And adolescents can be cruel and unthinking. I had my own experience with boys and talk and humiliation in junior high school. I was labeled a "Slut." Stuff about me written in the bathrooms, names yelled at me in the hallways, shunned by my girlfriends...the works. Of course, it was an exaggeration...something that snowballed way out of proportion. But that didn't prevent it from stigmatizing me for years. I know that it scarred me emotionally as I went on in the following four years to make choices in my sexual life that, frankly, I'm probably pretty fortunate that I made it through intact.
All I can offer you in the way of condolences is to let you know that it will fade. As you become more self-possessed you will be able to let it go. You will realize that, at that age, people say things like that just to be hurtful...not out of any basis in truth. You are a beautiful young woman and I think any grown man with an ounce of maturity will tell you that there is no such thing as an ugly vagina.
It just goes further to prove what idiots kids can be at that age.