Only 1 person in this thread has it right: you have sleep apnea.
I'd go get a sleep study done, but from what it sounds, you have severe sleep apnea.
When your airway closes up, your oxygen levels decrease and your brain wakes your body up continuously through the night so that you can get air. When that happens, you have what's called mini-arousals, and your sleep stages are disrupted. That means that you're just getting a light sleep all night. I see it all the time, seeing that I'm a sleep technician and work in a lab that tests for it.
Go get tested.