I have been bullied on and off throughout life for all sorts of things, but as a rule i've also been rather skinny all my life too... up until this past year, that is. So perhaps my experiences have been quite different due to that, but I've found it doesn't much matter what it is or how much a person weighs, mean-spirited or jealous people will ALWAYS find something to criticize.
When I was a kid I was too scrawny, had chicken legs, braces, stringy hair and was too much of a nerdy, book-worm, tomboy. When I got older people thought I was a threat, accused me of wanting to steal boyfriends, being stupid, flirty, fake, bitchy, having an eating disorder... you name it!!! Now i'm heavier and apparently fun, sweet and local therapist... but still fat, dumpy and gross. I won't even get into my families tough-love approach to help.
The different results apparenly weren't an actual reflection of my personality, because I am still the same as always. The only thing that changed was my appearance... and people reacting differently to it. Which imho, are due to huge stereotypes both the skinny or fat encounter. People acknowledge only what they choose to, for whatever silly reasons.
So, i've experienced backlash regardless of size. A person just can't win in a world of impossible standards, there are too many unrealistic expectations, and everyone's got an opinion. A certain amount of inner self-peace and acceptance is key, however difficult, and letting all those insults and excess opinions roll off. My only endeavor is to be healthy and comfortable in my own skin.