When i watch swimmers facing the problems you have, it looks like they need to focus on staying afloat. This means flat position and lack of balance. Rotation is essential and breathing is just a part of the rotation. Your head should constantly be relaxed and you you should look down, at the same time letting air out through nose or mouth. When you need air, your head just follow the rotation while pushing out the last air. Your mouth goes just over the surface of the water and the air goes in automatically. I know that Terry is against pull buoys, but as a mean for practicing rotation, they can be helpful. Use the pull buoy, do not kick (you can even strap your legs together to avoid kicking), aim your stroke at being long and relaxed, do not cross over (lead finger always pointing forward). If you do that right, you cannot avoid breathing the correct way. I am not a swim coach, but it worked for friends I have tried to teach freestyle. It is worth trying.