My STBEXH had sleep apnea and there were nights when I could've just punched him in the face so you have my sympathy OP.
The hardest thing was when he stopped breathing and you'd wait for that massively loud pig grunt when his lungs would gulp in air. He'd wake himself up and then jump up and glare at me for waking him. 
He was 17 stone and I couldn't roll him over when he lay on his back.
The result for me? I ended up in hospital with cluster migraines. I had no idea of the connection but I'd wake up in agony in the early hours of the morning, day after day. I had a CT scan, spinal fluid taken, the works. No one had any idea what was causing them.
Then one night I woke up with a terrible screeching sound in my head, turns out the snoring was so loud that it was stressing me and I was grinding my teeth so hard in my sleep it was to the point of causing migraines.
When I slept alone they completely stopped.
We tried a snore guard mouthpiece but it was useless. I'd hear it sucking in and out of his mouth all night, and if he turned over to face me I'd get a cold whistling wind tunnel of stale cigarette breath blowing at my face or my neck for the night. Until it fell out and the snoring would start again.
DS tells me that he can still hears my ex snoring when he stays over his weekends, and some nights he has had to go in and wake him.
I can't tell you how much I appreciate my new partners sleep habits. His occasional snore sounds like a sweet Disney bunny snoozing in a sunny meadow.