Hi daisie
There's a couple of books you can buy on amazon, The Acid Watchers Diet and Dropping Acid which may help you identify dietary triggers and find alternatives.
If you use the search function here, search for reflux rather than Gerd and there are lots of posts. Have you tried things like not eating for a couple of hours before bed, propping your mattress up or getting a wedge pillow, again from amazon. Coffee, chocolate, alcohol and rich food made my silent reflux worse but I'm fine with them now. Mine started when I started hrt and stopped when I came off it. It was mainly in the progesterone part of the hrt cycle so perhaps yours is hormonal in some way too. I found gaviscon advance before bed helped but mine wasn't bad enough to need a ppi. The wedge pillow from amazon was also a massive help.
Penguin x