I'm naturally underweight, not anorexic...?

I'm underweight, below the 5th percentile. I think it's in my genes, because my dad is also skinny, and my brothers are too. I personally don't like the way I look. I hate how I'm so skinny and bony in my upper body and lower legs, but I don't like the way my thighs jiggle so much, or how they're disproportional to the rest of me. I'm trying to tone up, but it isn't working very well. Anyway, everyone around me always asks me "Do you eat?" or "That's all you're eating?" I do eat, I just eat healthy because my dad's a doctor, so that's how I was brought up. One friend of mine recently told me that her mom tells her to finish her food or she'll look like me. Seriously? If I call someone fat, I'm going to be called a arrogant b****. If someone tells me I'm all skin and bones, how am I supposed to take that as a compliment? With everyone looking down on skinnier people, with all the people criticizing models for being tall and thin, how am I supposed to like those comments? In a "rate this picture" question, many answerers said something along the lines of "I like the third girl, because the others are skinny so they're all judgemental b*****es and throw up their food. They're so ugly" Are all the "EVERYONE IS BEAUTIFUL EMBRACE YOUR BODY" campaigns a double standard? Everyone who's at normal weight or overweight should love the way they are, but all the skinnier girls should avoid salads at all cost and eat McDonalds everyday to make others feel better? Italian society criticizes models for being skinny, and disqualifies size zero's now. Why can't there just be models of ALL weights, not just skinny, normal, or big-boned. I know I strayed from the question a lot, I was just ranting. So how do I make my clmates stop getting annoyed by my weight?