What is a good diet for someone without a gall bladder who is trying to lose weight?

I eat healthy, exercise but it seems that no matter what I try I don't seem to be losing weight. People keep telling me to eat a low fat diet but the doctor told me that eating low fat is what killed my gall bladder. He said that everything in moderation. However it seems that if I eat too much protein I get sick, if I eat low fat I get sick. I am so confused until I am on the verge of just giving up. I try to balance it out but I don't seem to lose a pound. Can someone help? I need realistic help. I have a very understanding family but I don't want to make them suffer with special diet. I can prepare two meals for dinner if need be but it would be easier to just prepare one. Any suggestions? I am also looking for something long term. More like a life change as apposed to a diet.