For a long time I have assumed that I was bisexual I am attracted to women for sure and I thought I was attracted to guys but now I am starting to think that I might be a lesbian. I have had crushes on guys during my teens but looking back I think I was just trying to fit in with all my friends but I'm not totally sure. I can appreciate when a guy is attractive but I don't think I can ever see my self being with a guy but I don't know if this is because I don't have any experience with guys, I do have some experience with women although not much, being unsure of who I am I have avoided relationships completely. The thought that I might be a lesbian scares me and I want to talk to my brother about this and I know he will understand what I'm going through because he came out almost 8 years ago but I'm scared.
If you can visualize yourself being with a girl more better, and it feels more right than you being with a guy, then it's totally okay. It's also okay to not even label yourself and just go with the flow! But also, it may or may not be awkward, but you should somehow just come out to your brother and talk to him about it (if you feel sure he'll be totally cool with it). You never know, your brother might probably be super excited and absolutely be willing to help you, and fill you in with some of his experiences and insight. You might learn a lot!
I totally know how you feel. I always called myself Bisexual when I wasn't because I was in denial of me being a Lesbian. You really need to think about if you ever see yourself in a sexual relationship with a male. If not then you are most likely a Lesbian. I'm sure your brother will understand as well and he may even think it's awesome his sister is a Lesbian. (*hug*)