I need advice for wieght lose?

i have been struggling with my wieght since i was in middle school, all the excersicing and calorie restiricion isnt doing anything, in fact im losing lots of hair and my skin is getting ewe... i eat veggies, fruits, turkey, cheese, wheat bread and chicken... i stay away from fast food, too much beef and my only weakness is chocolate which i limit to dark chocolate and lil pieces... wtf!!!!! im 22 now 5'6'' and 190 pounds... i want to get to healthy 140 or so.. i have LOTS of water weight, i mean, i wont pee more than once in a day even tho i drink like a hourse... help!!!