i was bullied when i was a teenager, then i went home to get physically and verbally abused by my father. kids that young dont think about if theyre hurting you, they dont think about how you feel.
to your friends, you need to tell them that what they say hurt your feelings, and if they keep doing it, i would leave them alone. you dont need to be with anyone who makes you feel bad about yourself.
your sister and brother is teasing you also, they dont know that your taking what they say to heart. i would sit down and talk to them. explain to them that everyone has flaws and it's not good to tease anyone for any reason.
dont feel like a looser for posting a question on this site. i posted many questions and i m not a looser.
it comes down to how you feel about yourself, i know people can make you feel bad about yourself. sometimes you have to ignore them.