Since primary school (5-12 years old) and right through high school I've always had more female friends, most of whom I found attractive but that was never why I became friends with them, the attraction always came later. Generally I found that I was able to get on a lot easier with them and since I was never sporty, involved in sports clubs etc, I didn't have many close guy friends. Don't get my wrong, I spoke to everyone in my year group at school and never really had a 'best friend' but I would usually hang about with an all female/mixed group or all male group.
Personally, who gives a damn who your friends are? Different things attract you to different people and you may just connect better with certain people. I don't find it to be less masculine to have more female friends at all and I don't feel it either.