Putting my head on the chopping block here, I realize. But what the hey.
Most people are not suited for successful open relationships, in my humble opinion. And I AM referring to a functioning relationship -- not a buffet of indiscriminate sexual activity without personal ties (which would be something else altogether).
I have been in one open relationship in my life. (Hmmm, okay -- maybe more than one, yeah forgot about X and Z there, I was distracted.) I tend to be a secret romantic, but the first time I was getting over a broken heart. I needed time to get past that. I met someone who could make me laugh and we enjoyed just hanging out.
They also were mourning a breakup (engagement broken). We became lovers as well as friends and it was sweet, but both of us were very honest and discussed how we felt that we would never be falling in love with each other. Our feelings just couldn't go that extra half-mile, although everyone saw us as a couple.
We talked about it and decided we didn't want to give up what we had, but also didn't want to prevent each other from exploring new relationships -- that might become more serious. With the understanding that everything would change between us, if need be, if one of us fell in love.
Thus, was born our open relationship. We never had a problem with it, though one funny story is that there was a young woman who wanted to hurt me (over a misunderstanding). She didn't believe we had an open relationship and seduced my partner. Then she swaggered up to me the next day, intending to absolutely crush me by telling me she had slept with my lover last night.
After she was done talking, I smiled and said "Yeah, he mentioned that. He thinks you're really great."
She was flabbergasted and we actually got along really well after that, when she realized she had the wrong impression of me, completely.
Eventually, the open relationship ended. There was a huge amount of pressure from friends and relatives that wanted us to hook up permanently. Everyone wanted us to be this storybook couple And badgered the hell out of us.
And we went our separate ways, but remained friends until he got engaged again--and I sensed it was too difficult for his future wife to have me in the picture (even as a friend--which I totally understood and supported) so I dropped out of touch.
(Though when something terrible happened in their lives, I popped back up and his wife was really glad-bizarrely enough- even grateful that I had reached out, and she and I would hang out yakking on the phone. Then eventually I distanced myself again, when it was like, the appropriate thing to do.)
That was early days. However, generally I'm monogamous and enjoy being jealous as hell--open relationships take too much damn work!
P.S. Anyone that gives me a cookie or a bucket of rainbows here is asking for a good smacking! XD
P.P.S. And the above relationship started when I was 19 and he was much older. Some of you may have read the thread on relationships between younger and older people. In this relationship I was definitely the more dominant person, though I never abused that power.