I know!! xD I'm going into 7th grade now and have decided just not to bring ponies around to school. I wear the mlp shirt I have but I try to wear it subtly. Most people have forgotten that I like ponies except for my close friends who have to put up with the ponies referances all day.
and so this isn't entirely off topic, it isn't any of those people's business what you like or do not like. Don't even respond to them, don't even give them the attention or drama they're looking for.
One thing that might help, in regards to pony fashion, is just to say, "Oh, I saw it in the store and thought it was cute, like Hello Kitty." Hello Kitty has toys, and tons of little accessories, but lots of adults/young adults wear her face proudly! That's kind of how it is for me, anyway - I love ponies, I love collecting, but I also think they're super-cute as an emblem/mascot for a shirt! And just because you own a shirt doesn't mean you're ADDICTED (how many people have Hello Kitty shirts or purses and nothing else?), so no reason to give them any extra firepower if you can help it.
Sometimes, if people are giving you guff for something you like, I think it's best to just go, "Oh, I think it's cute," and shrug them off. If you try to defend it too hard, or explain exactly why you like it, bullies will latch onto that. But sometimes bullies will attack you no matter how much you ignore them, so if it's really bad, I would recommend talking to an adult, like your teacher/parents. They might be able to help, or even just offer moral support.
