You poor thing. I had morning sickness my entire pregnancy and even in labour, the moment hamish arrived it went. I know you probably didnt want to hear that, but i just wanted to let you know that there are other people out that there that have it longer than the "normal" 12 weeks they say you are meant to have it. I tried everything else well but the only thing that worked was actually having the baby (sorry to say).
Good luck with it though, you may find something that works for you.