But my sister is obsessed with her appearence. She's 5 8 and 120 lbs. and looks very thin. She's been known to go out to dinner with me and refuse to order anything as she "isn't hungry at the time and doesn't feel she should be forced to eat" or "isn't in the mood for the food here." She's told me she's the only one in the family who has a chin/jawline. She's spent the last 10 years turning down food at family gatherings and refusing to celebrate thanksgiving because it's an unhealthy day of overeating.
I feel like sh *t when she acts like this. In fact, the other day I was up at night being angry about a comment she made to me a few months ago. I had her over for a dinner party. I made plain sweet potatoes, green salad wtih no dressing and grilled chicken. appetizers were carrots, hummus and crackers. dessesrt was whole wheat vegan banana bread or brownies. she told me i made entirely too much food and spent most of the night complaining about how she couldn't possibly eat so much. She then went on to tell me a story about how when we lived together years ago all I wanted to do was cook and she gained 10 lbs and was so fat she really hated her body then. She said she blames me for it and tells all her friends that her sister made her fat at that time in her life.
I'm not saying you treat your siblings like this, but chances are they feel lousy about being overweight and feel even lousier looking at you losing weight - which no matter how hard it is for you, probably appears to them to be pretty easy. yes, they should be healthy - but that's up to them. And as far as looks - well, there are more important things in life than being thin and having everyone find you attractive (at least I think so, my sister would disagree. To her the most important thing in life is your appearence).
Your sisters might be perfectly happy with their lives otherwise and probably don't need reminding of how they need to lose weight. All you can do is set a good example and try offering assistance and advice if they ask or bring it up. Take it from me, the fat ugly sister.




Still not easy.