What she had said was altogether false.

Ever since I could remember I had watched courting male birds fight all over the farm.

After a couple had paired, and were nest building, the father always drove every other bird from his location.
In building I had seen him pecked for trying to place a twig.

I had seen that happen again for merely offering food to the mother, if she didn't happen to be hungry, or for trying to make love to her when she was brooding.

If a young bird failed to get the bite it wanted, it sometimes grabbed one of its nestmates by the bill, or the eye even, and tried to swallow it whole.