I don't understand the bitterness and jealously.  I have my own little concocted theory that a large portion of it is due to the conglomeration of their meetings (tumblrs) and all the talk of victim hood they share with each other. Misery loves company. I guarantee if you see a table full of fats at brunch they are talking about the cute, thin girls in the room. It's what they all can have in common.  20 years ago obesity was not as prevalent but there were obese people. I was friends with one, she was a very very nice girl. I was a bridesmaid in her wedding. She had to weigh 250 I'm guessing. I'm not sure where I was at at that time but it was in the 120s and I was 3 months pregnant. I lost touch with her years and years ago but never, in all the time I knew her, did I ever hear the term skinny bitch or anything in that category from her. at all.  I think a lot of what we are seeing now is heavily influenced by internet messaging groups.