@Lioness: there is one plausible explanation. A person I know of had a sex-change operation. Physically, he/she can neither be considered a true male (vital organs missing, physiology wrong) nor a true female (vital organs missing, didn't grow up as a female and thus doesn't really know what a female is except as a second hand experience). - Here my statements are valid for this person only, I'm not generalizing.
This person is openly "lesbian" today (a long time after the operation), since he/she didn't find men very... pleasurable or attracting.
Weird, yes. True nevertheless. And, kind of sad, since before the operation, he was married and a father of two.
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