Sleep time facial pressure; morning eye burning; air pressure in mouth

For more than 11 years I've been dealing with issues that I believe are related to GERD. My current symptoms are most common at night from a few minutes after I lie down until I get up in the morning and get some food and liquid.
Symptoms:
-Facial pressure builds when mouth is closed
-After a few hours of sleep my jaw pressures my mouth to open wide
-When mouth open I feel liquid dropping from forehead downward
-Some release of pressure w/side pressure on forehead & mouth
-During nighttime lips have air pressure behind and frequently 'pop'
-After 'draining' liquid from head/face occasional jaw spasms
Trying to find a solution has taken me to many doctors. ENT's, Gastro's and specialists within each discipline. I've had a Nissen Fundoplication which did not ease the symptoms. The greatest discomfort is from the lack of sleep. That is, I don't have much pain. I'm on a modest amount of gabapentin and I take OTC sleeping pills to help me get 4-5 hours of rest nightly. I'm 72 and otherwise in very good health.