Here’s the American Heritage Dictionary’s Usage Note on gender:
I have noticed the anthropological usage above to be widely followed in the realm of gender theory and among those with a liberal conception of gender roles.
Perhaps I’ve been using gender incorrectly then, as a new-fangled PC synonym for sex. I’ve also been under the assumption that liberal conceptions of gender roles have been mostly throwing them out.
While I’m mostly nonplussed at the OP’s attempt to define her status as a boy or a girl… I am heartily amused at the idea that Miller and I might throw that same “How you doin’?” at the same person. 
Well there’s actually two different types of psychological androgynity (leaving aside physical androgyny-clothes and hairstyles and such). You can have strong masculine AND feminine attributes all in one snazzy package, or you can be almost completely undifferentiated, meaning that you actually lack many readily identifiable masculine and/or feminine traits. “Pat” of Saturday Night Live fame is a notorious example of the latter, and naming just one off the top of my head, Janine Turner on Northern Exposure would be an example of a person with a strong androgynous personality.
I consider myself (hetero male) to be an example of the latter; am into several “guy” pursuits, but can appreciate more feminine-ish things (yes I coo at babies and other people’s pets) as well, have no problem crying at emotionally moving things, etc. This is the avatar I use on another board, and as you can see that figure has both aspects.
Are you me? It’s a funny thing, gender “roles.” And I absolutely cannot comprehend much of the male interaction in the world. As soon as another guy starts to get territorial and confronty with me, I find myself wishing he saw me as a female so that he would know better than to bother. Also, I could then express myself to my “girlfriends” just to get things out.
I have often been read as gay, not because of being stereotypically flamboyant or anything, I just don’t speak “macho.” At all. And it’s fine for those who do, but the expectations often get me into social situations where I am left confused.
There have been times where I have been in situations where it was appropriate to assume a female personality (in other words, costume parties or other circumstances catering to role playing) in which “girl me” has been unleashed. People are usually shocked at how casually I can slide into that role. In such cases, I have literally “passed” as female (voice, mannerisms, etc.) It isn’t because of practice, it’s mostly just because it is part of who I am and the comfort comes from coming to terms with that.
So I can relate to the feeling of being wholly heterosexual, yet possessing traits which most others believe are homosexual indicators. The way I look at it, I am so attracted to and fascinated with women, that I relate to them more. Still, I often take the occasional gaydar false alarms as a compliment. My not-so-masculine-ness is part of what makes me me.
I can totally empathize with both the OP and Charger.
I’m female, but as I often say, I make a lousy girl. I just feel…wrong…doing pretty much anything that’s traditionally female. I don’t own a dress or skirt, won’t wear heels, don’t wear makeup, can’t stand being around babies and small children, and get bored by stereotypical female topics like guys, kids, cooking, etc. If ever forced to wear anything that leans toward the feminine end of the spectrum, I feel like I’m wearing a costume or in drag. I’m sure a lot of people think I’m a lesbian–I dress like many I know and, with my short hair and lack of makeup, probably present a pretty convincing picture–but yet I have no sexual interest in women. I’m happily married to a guy who understands and accepts my quirks. So what am I? Mostly happy, but always with that bit of unease that makes me uncomfortable in my own skin. I’ve come to the conclusion that it’s not male I want to be–it’s somewhere in between. Androgynous. I hate gender roles, and I resent being expected to play one that in no way fits my personality. I just want to be me, and pick and choose from among the masculine and feminine traits that work for me, without being looked at as odd.
It’s funny, because this has kind of come up lately. I play World of Warcraft on a roleplaying server, and my primary character is a level 70 male blood elf mage. His personality is very gentlemanly/elegant, albeit with more than a touch of arrogance and ambition. I love playing him–but I won’t admit that I own a microphone, and do all my interaction in writing because I love the way people respond to him (and me) and I’m afraid that it will change if they know that I’m female. I do nothing to imply that I myself am male, but I also don’t discourage the assumption. So far only three people in my guild (four if you count my spouse) know the truth, and they won’t tell. I’m just a very immersive roleplayer (this particular character is always in character) and the thought of people relating to him as a female is just…wrong. So I keep it ambiguous on purpose, and so far it’s worked out well. It’s nice to have the outlet.
Your situation sounds a bit more complex than preferring androgeny to traditional gender roles. The part that stood out to me is the “misogynist” feelings you have. To me that identifies the issue as more than being transgendered or gay transgendered or even a gay transgendered drag queen. I don’t often suggest a trip to the couch, but there’s an awful lot going on here. You might benefit from someone’s assistance in mapping it all out.
I’ll just note that if this is your ideal for yourself, male or female aside, I fully approve. (And follow up to note that if you have female bits and dig guys, I’d wonder what you look like. 
)
I don’t mean this to be a cruel or judgemental statement at all, so please don’t take it that way. But it sounds like you have identity issues that extend way beyond just your gender. Your whole section about being hyper-feminine to contrast your brother and then trying to be your brother when he left sent up big red flags for me. I think maybe you need to start thinking about your identity in general, not just whether you want to be called he or she. I wish you the best of luck in your endeavor.
Shout out from a genderqueer, cisgendered gay man. I have to say, though, that if you’re having this much trouble labelling your gender, there’s precious little reason to think that any of us are going to be able to do it for you.
However, if it helps, yours is similar to stories I’ve heard before from other people – female-bodied people who feel at times like a gay guy interspersed with feeling like other stuff.
Let me recommend you some books that might help you process this stuff – and it is quite the process; for me it took years to work out where I’m going with this, even though I was quite certain through the whole process that I was at least not transgendered.
I can recommend:
My Gender Workbook and Gender Outlaw by Kate Bornstein
GenderQueer: Voices from Beyond the Sexual Boundary by Joan Nestle et al.
Both of these were really helpful on my path to my own odd little identity.
BTW, working on this stuff with a sensible therapist can help – the word in italics is important because one who’s not ready to help you deal with your stuff can really screw you up. If you’re in contact with a trans or genderqueer community where you are, ask those folks for recommendations.
Seconded. I haven’t read the other one.