I think that this is a difficult question for most women to have insight on because there is little in the way of male clothing that a woman cannot wear in public. Even a man’s tie on a button down blouse draws only a little attention or comment. To – hopefully – forestall a rash of naysayers, I recognize that a woman can “crossdress” as a man and try to create a convincing illusion of being male. If a woman does that it probably is the equivalent of a male crossdressing in tranditionally female clothing. However, my point is that women have much more freedom with regard to clothing than do men. A woman can walk around in pretty much whatever she wants and not draw comment whereas a man in a skirt or dress is always, always noticed and usually ridiculed if not worse.
So, all I can really say is based on my experience with a very sweet, gentle man I know who likes to crossdress. His sexual life is straight, but he says that he enjoys dressing up as a woman and adopting somewhat stereotypical women’s mannerisms as a way to just relax, to “get out of his own head” and have fun with a different persona.
I also understand that not all crossdressers crossdress for the same reason.
Undeniably, some gay or bisexual men do it as part of courtship.
Then there is the whole transgendered category, which is very open ended and hard to define. If a male truly want to be a female in fact it makes sense that he wishes to wear clothing which would enhance his feelings of being feminine.
All in all, I think it is an interesting subject but one which draws more attention to the individuals who indulge in crossdressing than is really warranted. I try to view it as a personal choice activity which is harmless and mildly embarrassing at worst and may be beneficial to the individuals who engage in it.