Hey, it's no problem, you can vent with us. I, personally, totally get it. I was going through the exact same thing when I was about your age. I was always happy and cheery and innocent, but people would always kind of ignore me and talk about me as well. Mostly things like how I was ugly or awkward or stupid (again, honor roll talking here .___.) wore weird clothes or whatever. Thing is, I tried not to care so much, but regardless I ended up going through a really insecure phase and that only compounded my problems.
I think in part you grow out of it, but in addition, once respect enters the picture it completely goes away. I changed a bit - not completely, but enough to at least blend into the background. That might not be a terrible idea. But at the same time, you do need to find who you are and keep your head up, and let them know that you really don't give two flying flips what they think of you
(sorry if that sounds weird, I know you don't like swearing so yeah censoring myself hehe o__o;). If they realize that you really don't care about those 'flaws' (they're not really flaws, btw), then they stop pointing them out to you. Let them know that you're not insecure and that you don't need them and that you can do things on your own. Work on your drawing or writing, since hobbies help when you're feeling moody (at least in my experience). If people are mean to you, sever all contact with them - don't try to 'kill' them with kindness or convince them that you're not xyz thing because that's not going to work. Now I'm not saying to be downright mean but they need to respect you and respect your space. So be polite, but don't try to be friends with them is what I'm saying.
Lastly, I'm going to finish and say that it's really better to have no friends than bad ones. Even if you feel terribly lonely on the inside, don't let them know. Make them think that you're totally okay the way you are, and if they want to be your friend then they're really going to have to value you. You'd be surprised what it can do. I went several years without too much social interaction/close friends but when I finally did come out of my angsty/depressed teen phase to make friends, they were some of the best, if not the best, that I've ever had. Even if you just have one real, true friend, well... don't underestimate that. They can really turn your life around. And one true friend, in my experience, is more emotionally valuable than 50385038097978592385732 random, eh... female dogs...

Anyway, hope that helps. Just my two cents pitchin' in as always. Hope things get better for you soon.

Your friend,
Twin~