Okay, I think that helps. So with no gravity, the motor thrust will be acting exactly aligned with the long axis of the rocket and AOA will be zero. Therefore, no turning and a straight flight results. When gravity is applied there is a slight reduction to the vertical component of thrust and consequently the net trust is no longer exactly aligned with the long axis of the rocket. That causes a non-zero AOA. The fins then correct the AOA so that the long axis of the rocket is now flying at zero AOA but the net thrust is still not aligned with the long axis so the trend continues. This will cause it to pitch over into a more and more horizontal orientation. The longer the motor burns the more horizontal it gets. If it continues long enough, it will even pitch down. Eventually, when it is going straight down, the thrust and gravity vectors will both be exactly aligned to the long axis of the rocket. At that point it is flying at zero AOA so it will maintain that orientation from then on. Until impact.
If it was flying in a vacuum then there would be no gravity turn. It would just go in a straight line at a non-zero AOA.
I apologize for the diversion to this thread but I learned something today. Thanks.