Striaght Versus Gay or Bi
It seems that most of you are defining one's sexuality by actions, when I would submit to you that it's actually a matter of one's thoughts. Some years ago I took a college course on human sexuality in which the professor once posed the question: Which of these men are gay?
1. A married man with three kids who has only had sex with women his entire life, but all of his sexual fantasies and the porn he enjoys are centered around sexual acts with men.
or...
2. A gigolo who primarily services male clients and got into turning tricks to survive on the streets after running away from home as a teenager. All of his fantasies and sexual activities outside of making money are with women.
Taking the question one step further, is a man gay (or bi) if he engages in giving and receiving oral and anal sex to men, but he's not actually attracted to men? How could that be? Well, the turn-on might be something like submission and/or exhibitionism.
Certainly, it is easy to label a given sexual act as heterosexual or homosexual, but defining a person as heterosexual, homosexual, or bisexual is not that simple.
The reality is, since nobody can truly know your thoughts except you, you are the only one who can actually define your sexuality - and for many people even defining their own sexuality is difficult!