Masculinity and Femininty challenges

For those who don't know me, I'm not a girly girl. I rarely wear dresses, make up is only used for performances and job interviews. I keep my hair short specifically to not deal with styling. So there's that, but I have a weakness for the new My Little Pony series and I have a bit of a want to sew. So my boyfriend jokes that I am a girly girl. But he has long hair and also has some signs of being a brony.
My question lies not in am I a girly girl or is my boyfriend masculine enough, its why does it matter how masculine or feminine we are? The reason I ask this is sometimes when he teases me about being girly, I catch myself being defensive. Does it make me less of a feminist?Is it the ego that I've built up of being one of the guys, and that to be one of the guys in some groups, losing most femininity is almost essential? If so, what does that say about American society? To be in  a man's world you must assimilate to fit in? Then what happens when at times its just not you?
Dealing with masculinity and femininity is a tricky feat. And most questions tend to lead to more questions. So have fun thinking these questions over dear readers.

A little biased no?

So why is it that when you go in the DS and Wii section, its almost overwhelming how many imagine whatever, along with ballerina, cooking, babysitting and other similar games designed just for girls. Go to X Box and PS land, there is maybe a DDR game, or the Twilight trivia game, but not much in specific "girl games". Which leaves all groups in an awkward position; who's the more correct: Nintendo for having a small special market just for girls, or Sony and Microsoft, who don't have much in the way of specific market, but most games tend to not matter until on a microphone what gender you are?
          Of course Nintendo tends to aim for a much younger group than either of its competitors, but does that justify gender stereotyping? The one game I saw that was really made for young kids on X Box that was geared toward children that wasn't part of the Lego series was the Marvel Superhero Squad game, which is aimed for 5 year old boys.
          Sure there are some movie games on all systems, but that doesn't mean much considering that the game is, to nobody's amazement, a marketing tool over all. But look next time you go to a game store at what games are aimed at girls and what are aimed at guys and what systems each game is on.
           Why gamers that are way past this age group should care about these dumb games is simple: games made for young kids are used a lot as teaching tools. Whether this be in playing house, or memory, it teaches either using logic, or what roles are seen as normal, a lot like play fighting in the animal kingdom, its training. So think about what the games are teaching the girls. Although cooking is a good skill, why not an imagine fire fighter, or ace attorney mama? I'm just saying, why not do more in the way things that girls should do and do the same with the slowly appearing similar boy games?
 
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Just saying, cooking mama games are fun, so why not executive mama?