Why are the girls around me so stuck up?

I need help. The girls who are at my school, church and hobbies are so stuck up? They whisper to each other, giggly stupidly and maake fun of me. Now I LOVE my body. I'm 4'7 and now weigh 93 pounds (I just lost 5!) so I'm pretty healthy. They, on the other hand, are a few inches taller and weigh about 75. I know being thin is good, but I THOUGHT you were supposed to wait until you're older to worry about skinny. My doc and parents say I'll be a slim woman, so I'm not that panicked about weight yet. Also, they only wear jeans with rips. Never would they be caught dead in leggings or slacks. When they wear skirts, they are inches above the knee! They are only twelve! C'mon. They also make fun of my singing voice, which is becoming operatic and mature. It just don't make sense. Oh, and I get mocked because I am a BIGTIME reader/writer. They really are the little-short-skirt-with-a-big-attitude drama queens. To church, they wear skimpy dresses or one-piece swimsuits with skinny jeans on the bottom. They say they're so smart when they are actually idiots. They are always texting. When, four months ago, I thought I wanted to be friends eith them, they turned me away form their little dumb chat circle. They never get in trouble for their ways. Help me?