First, the misconceptions. Bisexuality does NOT mean loving two people at the same time. That is a comletely different subject, called polyamory. That will be discussed on a separate page here once I get it written or you can check out what I already wrote here and here. Nor does bisexuality necessarily mean that you must have a partner of both genders at the same time. Bisexuality is NOT the same as having an orgy.
Bisexuality, in my frame of reference, simply means that I will not limit my choice of partner based solely on the gender of their body. I was happily married for 12 years...well, married for 12 years, happily for most of them...to a male. I knew from the moment I laid eyes on him that I would marry him. Some part of me knew he was my soulmate and my teacher and my partner. And I learned a lot from him and part of me still loves him on that soul level, but the time to express that love in an intimate relationship is gone. I met my next soulmate online and she was the most wonderful woman. I knew from the beginning too that she was a soulmate, but for several months denied the love I felt for her because she'd given me no indication that she too was bisexual-- mainly because she didn't know until she realized that she was as in love with me as I was with her.
How could she have NOT known? The same way I didn't know for the first 30 years of my life. Aside from the social stigma associated with bisexuality (and I sometimes think it's worse for bisexuals than for gays and lesbians because many homosexuals can't understand bisexuality anymore than heterosexuals can), there is an attraction to the opposite sex, so the bisexual may not realize they're bisexual if the first several people they're attracted to happen to be the opposite sex. There is also denial, which is still a very strong deterrant to admitting one's bisexualtiy. I can look back on my life now and see that I had several crushes on women in my life that I never admitted to until I accepted and admitted my bisexuality to myself. There are religious reasons-- many faiths still place a heavy stigma on an orientation other than heterosexuality. I know that my own religious upbringing had a lot to do with my early beliefs concerning bisexuality. So discovering one's bisexuality isn't always as clear cut as it appears for most gays and lesbians, who are attracted only to those of the same gender.
I personally feel that bisexuality is "truer" to our spiritual nature because I don't believe the soul has any gender. I realize the need for heterosexual relationships since there is a need to procreate. But all love is not meant to lead to procreation. That too is another topic...Love is love and will not recognize any boundaries except those that we put in place of love. I have chosen not to allow the boundary of gender to stop love.
I have also come to realize that one's "sexual orientation" really has nothing to do with who one has sex with. There are plenty of "straight" folks who enjoy an occassional same-sex sexual encounter but who are still heterosexual. Conversely, there are gay men and lesbians who enjoy the occassional "straight-sex" sexual encounter and who are NOT bisexual or heteroseuxal. One's orientation is all about Love: who you fall in love with. You can control who you have sex with-- that is always a choice (assuming of course that it's not rape or molestation). But you sure can't control who you fall in love with. Lesbians, while they may enjoy "straight sex" only fall in love with other women. Heterosexuals, while they may enjoy "gay sex" only fall in love with the opposite sex.
So that is what bisexuality is to me. If others can identify with what I've written, I hope this gives them some encouragement to accept themselves if they have not already done so. If such encouragement is not needed, then perhaps a little encouragement on the days they feel down on themselves for whatever reason.
Read about discrimination I've faced from the Boy Scouts of America because of my orientation, despite four years of active participation in my sons' pack.