I don't quite understand why the same thread seems to get posted under a different name over and over again. I'm not knocking the thread, or the original poster, but it's a bit redundant. It's just an ongoing cycle of people saying "yeah, you're either gay or bi" or "why do people get so hung up on labels? Labels aren't important, and they're the problem." Well I call bullshit. Heterosexual and gay men and women may have engaged in sexual intimacy with some of the same sex or the opposite sex, whether for experimentation or trying to fit into the mold brought about by social norms. However, if that behavior is continued, meaning you've explored your curiosity to the point where it's no longer a curiosity, then you are who you are, and it is what it is. Deal with it. {Example} If a person tries drugs once, then they experimented. If they continue to do so, then they are drug user.
Labels will continue to exist until we learn to embrace them, each other, and ourselves. When we as a people can learn to be more accepting, then the labels will die. Otherwise, it's all a facade. You're merely fooling others and yourself.