Its horrible, trace, so sorry your dd has it. My dd has silent reflux, but its a lot better now - she's 7.5 months - and some of that is down to meds: she's on Ranitidine (helps a lot with the pain) and Domperidone (helps them digest faster, so they don't 'back up' with milk). She was put on these at 8 weeks, when she was diagnosed with a 'floppy larynx' - laryngomalacia - which will sort itself out in time, but basically makes things worse breathing-wise for the first year.
Gaviscon helped my dd not throw up, but did nothing for her pain or digestion - I strongly recommend asking paeds and/or GP for Ranitidine and Domperidone. Or at least Ranitidine.
The only other things I can add, helpwise, are that my dd still sleeps on a slope (pillow under mattress) and used to sleep better in her bouncy chair, placed in her cot for safety. She had bronchiolitis at 4 weeks (very seriously) and her breathing was rubbish for ages, due to her larynx problems - and the reflux. The meds helped her breathing problems as well as her pain, as acid reflux swells up tissues which then block her already small windpipe.
She also did better with lots of small feeds, no big ones. And being held upright for quite a while after a feed. And being patted under the bum or just sat forward to burp - not patted on the back, which pushes acid up at the same time.
Am rushing, sorry, hope some of this makes sense - I know how scary it is, and how stressful and upsetting, and really hope things improve soon! xxx