Hi, and congrats on your weight loss. Its not that she is jealous of you, remember when people would comment on your weight? That's why she is angry with you. Out of all people you should know how if feels to know your gaining a little weight and someone tells you. Its hard for me to not say anything to friends and family that use to tell me i was fat and now they are gaining weight and im losing. When she says something about her weight just say, lets go for a walk together or something like that. Don't put her down even though you think your not and i understand your not doing it on purpose. You just have to becareful on what you say esicially to teenagers.