My gastric bypass was 2 weeks ago so I haven't had a chance for regrets. I am writing to let you know that I too had a Nissen about 10 years ago. It helped a little since my GERD was so bad that I literally had acid burn in my mouth. Over the years the problem has returned to its original state. With the bypass, my surgeon said the Nissen had come apart so he did away with it. What? I am still in panic mode though he said he took measures to disable the nerve that activates acid secretion. Yeah, I know, I don't get it either but my husband says there are no longer any protons to inhibit with acid blockers. I will keep asking the surgeon to explain it until I finally get it. The surgeon said I will have the reflux for about a week and its been two. I don't know the difference in reflux and food backing up due to overeating.
Due to the Nissen I could only have a gastric bypass, none of the other lesser procedures. It sounds like the Nissen would have been required regardless of the WLS. Mine was. I understand your frustration and pain. I was so happy when they told me they could fix my GERD that I literally cried and to be honest, any relief was a plus. I support you.