Scapegoats are easy targets because at some point you gave up sticking up for yourself and accepted the abuse.
I remember begging my mother to believe me when she caught my sister doing something and she'd lie and say I was doing it too, so I'd get hit along with her.
A very helpless feeling.

The only way to stop being picked on is stand up to them. It's scary, but get indignant like everyone else when their being maligned. If they go, 'yeah, right' when you say 'chocolate' -- don't ignore it. Have a terse response, ' okay know-it-all, what IS my favorite flavor then?!' or 'why'd you bother to ask if you decided for me.' Something like that. It works, because it puts it back on them. They'll try and make it seem you're overreacting, but you're not.

I know it seems immature, and I used to not say anything and just let it go and take the 'high road' as they say, only to eat myself out later about it, but the older I get the more I'm convinced we never really get out of high school!

Just give like you get.

Good luck