mixed connective disease have high associations with dry eye and dry mouth. By far the most common cause would be the eye drying, sticking to the lid and not wanting to open. Start by getting a 'hygrometer' which measure moisture in the air and putting one in the bedroom keep the humidity around 40% during the dry months if necessary use a room humidifier. Make sure no air vents create currents across the bed. Do not sleep with your face in a pillow or on you face if you can help it. If gels don't help try regular artificial tears, different brands, if not help try a lubricating ointment like Refressh PM or Lacrilube or Duolube. There are some diseases such as myastenia gravis that can cause inability to open eyelid but this is not at all a typical description.