Hypothyroid and weight loss?

hello everyone i need help and hopefully someone thats benn or is in my situation can help. I have hypothyroid which is a thyroid disorder that slows down your metabolism and makes it difficult to loose weight. And the worst thing abouth it is that it causes weight gain as well :( i have tried so many things to loose weight and nothing seems to work. At one point i was successful at loosing weight but gained it all back plus more because my thyroid got worse. Some people tell me its pointless to exercise because i wont get nowhere with it because i wont loose any weight, please does any one know what i can do. i have asked doctors and i get no answers. i am on levothyroxine to treat it but its also not making any improvements. thanks for reading. i would also really love to know of any sites i might go on to find info on hypothyroid and weight loss.......