Welcome to Healing Well! Sorry to hear you're struggling. You're definitely in the right place, as there are many here suffering from GERD. It is true that weight gain can increase GERD symptoms, it doesn't change the fact that you're suffering.
Since lying flat creates more reflux symptoms for you, I suggest that you elevate the head of your bed. You can put blocks under the legs, or buy bed risers. Elevating your bed in this way allows gravity to help keep the acid in your stomach. Using pillows can cause your body to bend in the middle and create more pressure on your stomach, and thus more reflux.
Don't eat ANYTHING 3-4 hours before you go to bed. I don't see in your post that you've been prescribed any acid reducers. Try an over the counter medication like Zantac (Ranitidine) to start, and see if it helps. There are over the counter PPIs like Prilosec (Omeprazole) as well, if the Zantac doesn't work.
With the problems you're describing, it seems like you should be seeing a GI specialist. I suggest that you pursue that with your primary care doctor.
I expect others will be by to weigh in and add their own suggestions and support. Good luck!
PS...f you do a Google search for "GERD", you'll find lots of helpful information about food triggers and things you can do to help your situation.
Nissen Fundoplication 2/09
"Whatever you fight, you strengthen, and what you resist, persists.”
“Worry pretends to be necessary but serves no useful purpose”
“Accept - then act. Whatever the present moment contains, accept it as if you had chosen it. Always work with it, not against it.”