Nonbinary Gender: Sometimes a Compromise in Multiple Personality 

Multiples with both male and female alternate personalities may appear unisex or nonbinary as a compromise (2, pp. 110, 120). Of course, people who have multiple personalities, whether or not they appear nonbinary, are not mentally ill, unless it causes them clinically significant distress and dysfunction.

Added Sept. 7: When nonbinary, but not multiple personality, is recognized, the latter is being more discriminated against, as usual.

1. Wikipedia. “Non-binary gender.” https://en.wikipedia.org/wiki/Non-binary_gender

2. Frank W. Putnam MD. Diagnosis and Treatment of Multiple Personality Disorder. New York, The Guilford Press, 1989.