Generally, when a person sleeps, their mouth completely relaxes. The tongue moves back towards the throat, the tonsils collapse inwards, and the soft palet descends, effectively closing off the mouth from the throat. Apparently you're supposed to be breathing through your nose, eh? But my nose has a deviated septum and enlarged membranes, so not enough air gets through there. So when I sleep, I don't breath very well.

This is not something water will help.

Losing a substantial amount of weight may decrease the size of the membranes a little. The mask/forced air approach simply keeps my airways sufficiently open so that I can breathe. However, it's not effective for everybody. The surgery to the nose would correct the deviated septum and reduce the membranes. Not a big deal, and quick recovery. Besides, then I wouldn't always be getting my nose out of joint!

The throat surgery is a little more drastic, and a last measure. But even it is little more than a tonsilectomy, which is a routine as a surgery can get.

So even if I go under the knife, I'm not worried.