Depressed, weight gain? please help?

i have dep. n im on lexapro, but here's the thing, since i started taking lexapro, i have gained 20 pounds, so i now weigh 130 pounds exactly...im 5'4 and a female, 17 yrs. and all my sister just told me right now that im fat, and her husband told me i was chunky. As if i didnt have enough being suicidal and depressed, now im even more deppressed cuz of the weight gain and the comments , i just feel like bulging everytime i eat so that i can get back to 110 pounds.....please help!!!!!!! i dont want to end up bulimic!! i've tried dieting, but i get soooooo hungry, please help, i have no one else to turn to, my fam members r telling me im fat, n i told my bf that i felt like throwing up, and he told me.."what the f is your problem, u know what dont even talk to me"......so i have no where to turn HELP