As I'm nodding off to sleep I involuntarily and violently gasp for air. This happens a couple of times and only when I'm starting to fall asleep.
I copied this statement from your post. this is caused by sleep apnea, and I am going to assume that it happens when you sleep on your back for the most part. As your body starts to relax so that you can fall asleep I believe that your throat and or tongue relax and that gasp of air is you waking up and in turn your oral muscles wake back up and there you are sitting there wondering what happened. This is the experience that I have had. Try getting an oversized pillow and sleep on your side or stomach. Hope this helps with that little part. Jim.
Blessed be the God and Father of our Lord Jesus Christ, the Father of mercies and God of all comfort, who comforts us in all our tribulations, that we may be able to comfort those who are in any trouble, with the comfort wich we ourselves are comforted by God. 2 Corinthians 1:3