Heartburn that bothers me

I am a 29 year old male and I've had acid reflux for over 10 years. I have been on nexium during that time and it helps, but I don't want to stay on it anymore. I've completely changed my diet, as now I am Vegan and Im starting to become gluten free. This has seemed to help about 50 %, and I only take about half the nexium pill now but I still can't come off of it. I was diagnosed with a hiatus hernia a couple years ago but I do not want to get surgery for that and I believe it can't be all the problem here as I had the reflux even before I had the hernia. I have constant gas ( belching) after food and heartburn that bothers me most up near my neck throat area. Its a feeling as if my food isn;t being digested and its coming back up. I've seen many specialists and tried just about everything. There must be something I can do to Cure this.. Any thoughts would help me so much. Oh and Im very healthy otherwise, the only thing is Im a bit underweight and I urinate a lot... Thanks so much