Wow. You sound EXACTLY like me with the exception of the Nissen procedure. Look up adhesions and small bowel obstruction and I bet you'll find the symptoms are what you're dealing with.
Adhesions are just scar tissue that forms after any inflammation or injury - like surgery. Sometimes it forms on your bowels and causes them to twist and untwist. When the waste can go through, you get pain, bloating, nausea and vomiting. To add to the fun, the scar tissue doesn't show up on tests either, so you have to convince a surgeon to do an exploratory laparoscopy to at least look in there and see what's going on. The surgeon can cut those adhesions down right there and then. Of course, the problem is convincing a surgeon to open you up without some kind of test giving him a reason. With your past surgical history and current symptoms, I think it would be worth it look into.
I've dealt with adhesions and obstructions for 10 years. Guess I'm just one of the "lucky" ones who grow the stuff like weeds. Like you, I take phenergan every day along with pain meds. The biggest problem is eating and maintaining decent nutrition. Do a google search on "low residue diets". It really helps with the pain factor to avoid foods with a lot of fiber.
Have you had your kidneys checked for kidney stones? Kidney stones are very painful and when they move out of the kidney and into the uretra it can cause the colon to shut down and let the barfing begin and because it shuts the colon down you can get constipation that is awful. Sometimes when you throw up and have nausea it isn't about the digestive tract so much but maybe another organ not being able to function properly. Yes, this did happen to me for almost 8 months. The pain is AWFUL and drops you to your knees and you sweat and throw up and basically feel like death. This may or may not be your problem but I would include it in the search. Good luck to you and God Bless!