That's a damn good question Nessa! I think it all boils down to not allowing fear to make decisions for you. Jealousy is rooted in fear...the fear that you will somehow lose something precious if a contemplated action takes place. Usually it's the fear that somehow you just aren't attractive enough to have your lover's heart and someone else can easily take the attention of your lover away from you. It's also rooted in the fear of being lonely which masquerades as the fear of being alone.
A poly person accepts that jealousy means there is something out of balance and begins to look for the true cause rather than allowing fear to run them in circles. A poly minded person accepts their lovers at face value...we don't assume our lovers are lying when they say they love us and we don't see love as a limited commodity. In other words we accept and believe that it is possible to love and be loved by many people without the love being diminished. Time, however, is limited so you have to be able to deal with limmerance (new relationship energy) while living and building you other relationships.

Now do I think this mindset is limited to polyamory? Hell no! See the diference between happily monogamous people and happily polyamorous people is just the number of lovers they have. The trick is leaving the fear of loss behind, trusting your partner (or partners), good listening skills and good problem solving skills...and after all of that being happy, safe, secure and above all proud of your choices. There is no need to feel threatened by someone else's choices they have no bearing on your life choices.

What I'm trying to say is don't let jealousy rule your decisions and don't be ashamed to say that you are happy with your monogamous relationship. Polyamory is not more enlightened or natural and it's not about your loved one getting to play around while you sit at home alone...or worse watch them ignore you while having the time of their lives. Truly, finding out what it could be is the journey and it's so individual that boxing it up in neat phrases and rules limits the wonderousness.

Certainly everyone wouldn't choose to have a polyamorous relationship but jealousy shouldn't be the deciding factor! It is an emotion like fear (in fact rooted in fear) that can be faced, however unpleasant that prospect may be. The deciding factor should be whether you are happy and well satisfied in a monogamous relationship. If you are then you have already made the choice that is best for you...there's no need to justify it anymore than that!