Im not sure who I am...advise?

I've been a certain way my entire life and I have people who love me for who I am now.. but recently a new employee has made me second guess myself. over many years of my childhood I have felt more like the opposite sex than the one I was born as.. and felt guilty whenever I dated someone when i ended up feeling like Im not who people think I am, or who I want them to think I am. but those thoughts and feelings always pass.I am attracted to both females and males and so I always assumed those feelings were justified by my upbringing.

for the most part I'm happy with my life in general, and i like to believe that I am happy with who I am as a person. I never had those kinds of feelings in a long time.

when He started working we immediately became close as I am his manager and spend the most time with him training.
He is openly gay and is so open about his life with me, and I find i have no problems opening up to him about my personal feelings about life as well. But recently he told me I don't act like most do and he likes that I can be that honest with myself and my sexuality... and it made me realize that i'm not.

I am now questioning everything about me and my relationship with my boyfriend I love and I've been with for 3 years ... which I'm now feeling guilty about.. because what if I'm not suppose to be the person I am..and I'm just me inside someone else's Ibody...and how do i even go about telling someone I care about, something like that?...