I have separated the head with a seam around the neck. There is also a seam from the bottom back of the neck to the forehead. I don’t understand that my unwrap looks so distorted?
For one, Blender warns that your object has non-uniform scale (top right). Ctrl+A -> scale in object mode to apply scale. Get rid of ngons in the mesh, then unwrap again.
If that didn’t help and the seams are like they should, you could try changing the unwrap method on the operator panel (bottom of the tool shelf or F6 after unwrap).