I am very new to the poly life so I am joining in not based on what I've seen but based on being the bisexual woman.
I am just going to talk about what brought me to this life. I have been bisexual for as long as I can remember, although I did not come out to anyone (including myself) until after the end of my 1st marriage almost 10 years ago. Part of the reason that marriage ended was due to the fact that I was forced to act only straight. My ex was not interested in me being with anyone else, female or not. I moved on and made sure my next partner (now my husband of almost 7 years) was ok with me being with women. However, even with an open relationship I was not happy. I feel that, for me, I am both attracted to men and women. Therefore, I want and need both in my life simultaneously. However, I still want the stable long term partner, not just a FWB. So keeping in mind that I am bi and need both and the fact that I want the long term relationship with both parties, it is natural to me to want a situation where both of my partners live with me and are involved with everyone involved. (Hope that made sense to you guys.)