Hi Cupid04,
It seems very unusual that you would have such excessive tearing whilst sleeping that your face would be so wet on waking? Usually if you sleep with your eyes partially you are more likely to get an evaporative effect of the tears causing dry eye symptoms. These symptoms are usually grittyness and blurring on waking with sometimes watering as a reflex action to relubricate the ocular surface. These reflex tears are usually more watery than normal tears and can generally overflow. This can often be seen by cold/wind stimulation in dry eyes suffererers.
In your case I suppose your head position whilst sleeping could let the tears flow away from the natural drainage of the tear duct and the overflow would be down the side of your cheek touching your pillow.
Although as Sqad says ' could one lacrimation that much?'.
Do you have excessive tearing at any other times?
Any other dry eye symptoms such as intermittent blurring, grittiness, stinging etc?
Have you tried any ocular lubricants before sleeping such as Lacrilube to see if this helps?
What did your optician say about the health of your eyes and tear production and their quality?
The main question is do you sleep with your eyes partially open? Has anybody told you this before?