Gay, bi, and lesbian people, tell me why do some of you base your entire identity on your sexual orientation?

One thing that confuses me is how people base thier entire identity on their sexual orientation. I am a bisexual transguy, mostly gay though but this is not my entire identity. I am bisexual/gay, but I am also an animal lover, I love music (metalica, evanescence, avril, katy perry, linkin park list goes on and on), I have a killer sense of humor, I love watching people get pranked, I like plants, I hate bullying, I hate vegtables (except corn and potatoes) and so many other little things about me. I am so much more than just these labels people try to pin on me and myself. Again I hope I do not offend anyone but why base your whole identity off of your sexual orientation? GLB people out their, do any of you agree with this? Tell me who are you besides Gay lesbian or bi?