Haha. Most of my friends are gay, too. It is kinda funny. I tried to be a lesbian for a year or so in college. Didn't work. I just wasn't all that attracted to girls. Now I'm pretty asexual, although I can appreciate hotness in either gender. I'm romantical attracted to guys, though. I just don't like that I feel so feminine when I'm with a guy.
As for the behaviors, growing up I was of course told I wasn't lady like, but my parents didn't really push it. They wanted a boy from the beginning and ended up with four girls, so they dressed all of us like little tomboys and my father pretty much treated us like we were boys (my mother's kicking herself for that now that she thinks I'm "a dyke" [her words], no matter how much I explain I like men). I can only remember a few instances of my mother trying to make me act more like a girl. She pretty much just excepted I was a tomboy.
Other people only pointed it out every so often. One of the most popular boys in school was actually disappointed when I started wearing girl clothes in 8th grade (went back to boy shirts in 9th, though I kept the girl jeans) because even though I wasn't popular at all, he still thought of me as the cool girl who played basketball and snowboarded. In high school I was just a JROTC girl, most of whom were seen as "manly" anyway. People pointed out a lot that I never showed emotion an kept a cool head through anything and at Sea Cadet boot camp the other girls relied on me to keep everything cool and comfort them because I was the only girl who didn't cry once during boot camp. I was just a strong, solid presence, which I didn't think of as male at the time, but now I do. And I wore a dress to prom, although everyone and his mother (including all my teachers that were chaperoning) made a huge deal about how weird that was.
Then when I went through my denial stage in college I forced myself to adopt a lot of really female traits (going mostly off what trans websites were telling ftms NOT to do) and now I'm having to unlearn. For instance, I started purposely standing with my legs close together with my weight unevenly distributed and now it feels weird for me to stand like a man, even though I did for most of my life. I also have to force myself to take up more room and for some reason during my denial stage I got into habit of yelling "yay!" like a girl whenever something mildly good happened... It's something I NEVER would have done before trying to be more like a girl, but for some reason I'm now having trouble breaking the habit...