Have you tried flipping the pregnancy pillow around?
I have trouble sleeping on my side, but I wedge the pregnancy pillow by my back to get at like a 45 degree angle, which has been working this pregnancy. Last pregnancy I piled up pillows and slept on my back but with an incline so it didn't affect blood flow.
I have never been a back sleeper, always belly or side. But the last couple months, even with a pregnancy pillow, I have been rolling onto my back. It’s like the urge to sleep on my back overtakes everything and gives me extra strength and mobility, even in deep sleep. I tried sleeping back to back with my husband to have more of a solid wall than pillows so I don’t roll over, but I’ve ended up rolling on top of him in the middle of the night💀 It doesn’t happen every single night, but when it does there’s no stopping me lol
I'm about 24 weeks preg and side sleeping is killing me. And now when i sleep on my back i wake up feeling like i couldnt breathe well. 😪 sometimes i wanna sleep in a chair for real