Ukyou was never really a guy.  Ranma is not such a moron that he can't 
adjust his viewpoint.

I see you haven't answered my question ... Would YOU marry a girl who you
believed to be a male for most of your life?

Now you've changed your question.  You asked, would I marry a girl who 
used to be a guy.  Ukyou was never a guy.

To Ranma, she was a guy. She lived as a guy as well... the only thing she
didn't do was get a sex change when she was 6... other than that, she was
a guy, and acted like one, and lived like one ...

With regard to the second question, I'd say yes.  And that's Ranma's 
situation.

You'd say yes. But you don't have Ranma's macho self image to maintain,
do you? Ranma's homophobic, and marrying a girl who dresses, talks and
acts like a girl is a little too much on the iffy side to keep up Ranma's
'I am a man!' image ... Ukyou's only ever appearance in a dress was the
kimono she wore when trying (and failing miserably) to be a woman. Ukyou
isn't a woman - she's an okonomiyaki chief... Ranma needs to marry a 
girl, not a cook... He needs to keep up his image of being a guy, not
marrying someone who acts and looks like a guy most of the time ... he
also loves Akane. The only time Ranma may marry Ukyou is after Akane's
death, or when satan goes skating to work.

Kun-chan...