I've been attracted to boys who like boys for as long as I can remember, but I've yet to find that elusive guy who actively sleeps with both sexes. They either seem to be mostly-straight boys who are liberated enough to be able to admit when another guy's good-looking (and who might given in to the occasional drunken public makeout, eager to tap in on the chic value of queerness) or mostly-gay boys who like being platonically affectionate with their gal pals and will give them an occasional tongue kiss just for kicks. I've been involved with both genders myself and I'm definitely not biphobic, but most of the guys I've met who claimed they were "50/50" seemed to default to the heterosexual privilege of a relationship with women, or made claims that they were attracted to men sexually but not emotionally. I would love to meet a guy who's genuinely attracted to and interested in sleeping with both me and other dudes, but I'm beginning to wonder if this only happens in my dreams. MMF is a big turn-on for me but I don't really have much desire to pursue it with guys who aren't going to get into it with each other, too, and who are only doing it for the pussy.
(I guess I should add that I live in the SF Bay Area, so if it ain't happenin' here, it's probably not happenin' anywhere.)
Well, we do exist. There may not be a lot of us; (at least not out in the public eye) however, we are here.
If I meet a man and things progress to the point of intimacy, then I go for it. If I meet a woman and we move towards intimacy, I go for it. To me sexuality is fluid and gender is merely a tag which curses all of us from the day we are born. Over the decades I've been with several women and several men and each one has been a person with their own charms and each has set my motor running.
An encounter with a man and a woman is not an issue to me, nor is an encounter with 2 men. (Haven't yet had 2 women-other than in larger groups, which doesn't quite count since there was no emotional attachment). I have been the filling of a sex sandwich and I have also been the bread-for both with 2 other men and with 1 woman and 1 man. It's all enjoyable.
The world in general is not always at ease with the idea of bisexuality-many are stunned or offended by the idea that a man or woman would be able to have fulfilling relationships with both genders.
As for your 'right places' to locate these encounters, that may never happen. It's all a luck of the draw. Even if you went to sex retreats, swinger parties, orgies, etc. you would not get precisely what you seem to be looking for. You seem to want a gentleman who will be devoted to you; but still be willing to hop in the sack with another-trust me, that does not always make for a long lasting relationship as issues of jealousy could arise. (he could become jealous if you're getting off by another man or another woman, or even you might become peeved if you found he was making deeper moans as a man fucked him than he ever made while having sex with you-believe me when I tell you, jealousy is a dull edged but penetrating knife which glistens in the night).
Find a relationship with a person who makes your heart beat faster and sets your legs to wobbling, and stop worrying about whether or not they will have sex with another.