By default, I accepted the cultural norm of sexual-emotional monogamy for most of my life, but have identified as polyamorous for the last, ... let's call it twelve years. I've been with my partner, Kevin for fifteen years, but it took us a while to get around to mutually embracing a fully open-n-honest approach to loving together.
I actually had a really fine person I cared about, and had a brief sexual relationship with, ask me to be one of his several boyfriends. This was long, long ago, before I met Kevin. I turned him down because I had my head stuffed up my arse and believed at the time that true love is exclusive. Wow! It's amazing that I believed that, looking back.
I'm not sure it would have worked out with this guy, anyway. But he really did like me, and maybe.... But I was in love with another guy round that time, though he wasn't available. That would be the Derek I mentioned in my bloggy thingy.