I have tried everything...

So how long have you been doing everything like exercise, diet, weights? You have to do this regularly for about 6 months for you to actually see results. It doesn't happen like magic. That is why the term work-out is more appropriate here instead of exercise. You may be doing these things incorrectly if you say you've been doing them for quite a long and you still get no results.

Exercise should be done at least three times a week with an hour each, but it can also be done everyday for 30 minutes. Along with exercise you also need to go slow with your food. These things are not like something to be reached and stopped after you've achieved your weight goal. These things are supposed to be done for the rest of your life as very much a part of your existence like eating and sleeping are. So all I can say is, keep on doing what you say you are doing---exercise and dieting.

i dont know how much weight do you want to lose but the best solution is boiled vegitables and chicken. if you are boiling one kg of boneless chicken add 3 litters of water, one tea spoon salt and black peper to taste but not too much (max 2 or 3 pinches). when its boiled dont throw the water drink it with the chicken. this can be done with vegitables too but dont use more then 250 grams of potato per day if you are trying to lose weight. any one who wants to lose weight can use this.

Even though you say that it is not your thyroid, there could be another underlying medical issue. Your age might have something to do with it, because your metabolism slows down a great deal when you get older.

thats to bad but dont lost hope to get what you want and be couragous more and continue what you doing and i have some friend they the same like you they have a problem the same to you but they always believe that one day they will lose wiegth..just be patient be normal wat u are.