Oh I could have written your story! Dd is now 26m and a total delight! But but but. She is still on mega doses of omeprazole, still reacts to the merest sniff of milk, soya and egg, and still struggles with reflux when poorly with colds etc.
Things that helped.
Persevere with slings. Try a sling meet to see if he is happier more upright, as may be hunched over in some of the softer ones. But sling, pushchair, long walk for that crucial quiet time for you.
Agree with others who have said, try omitting soya. Are you still bf? If yes, could you go back to ebf, it's a good way of trying different things in your diet to see if there is a reaction. You can buy Nutramigen AA in a pharmacy, I think it's about £20 a tin, but could try that to see if there is an obvious difference if ebf not an option? Then present the facts as a fait accompli to the gp.
Weaning to solids, agree again with 4 day rule. I had an awesome spreadsheet lol, but was helpful in pinpointing blueberries as being serious wind inducers 
Papaya is supposed to be a good natural anti-acid. Banana is a bit claggy for their sore reflux throats.
Sleep. Ahhh sleep. Omeprazole was what fixed it, seriously. She still woke for feeds, once or twice, but none of the screaming abdabs like she had used to do.
Sorry you haven't any family locally, and that dh is sticking his head in the sand. Make sure you get to a childrens centre near you, for a wee break - our local one used to take dd and rock her and wander round so I could chat to mummy friends and have a 
Good luck though, it will pass, it will get better 