Who I am

Yesterday I came to realize that my friends see me as 'one of the guys'. We were talking about relations and I asked them what they looked for in a girl. We talked about the girls we knew and why they didn't fall for them. Then I realized that I'm a girl myself.
Most of my friends are guys, I treat them like equals, they treat me like an equal. Most of the time it means that we're talking about stuff like relations, girls, beer, parties, music, shows we've been to or are going to, sex, friends, people we used to be friends with. I forget that I'm another gender then them and talk about all these things in the same way as the guys do. My sister and her best friend, who also are part of the group of friends I have are a totally different story. They act like girls and are treated as such. When they enter the room, they tend to change the conversation into something totally different. They listen to a different kind of music then the rest, constantly talk about guys, love shopping, love going to a disco, hate going to shows by punk bands. Pretty much the opposite of me and my friends. But I've known my sisters friends for 11 years now and my sister for as long as she lives. We, Jerney, Sebas, my sister and I, were always together. We grew up and still live in the same street, I moved here when I was 4 years old.
It's strange that they are being seen as girls and I'm.. I don't know how I'm seen, not a girl, not a guy.

I need to forget about this gender stuff and just be myself. Why worry that I don't have a boyfriend when I love being single? But it keeps bothering me that my friends don't see me for who I really am..