Originally Posted by AllDayEveryDay
I just recently opened my heart and my mind to having a Monoamorous-Polysexual relationship and I am so lost.
Monoamorous-polysexual is "swinging". Essentially you would be a couple who takes on sex partners but somehow manage to not fall in love. In my opinion this is one of those structures which is built to fail. There is simply no way to determine, beforehand, whether or not you will develop romantic feelings for someone - certainly when you are already having sex with them.
Polyamory is having multiple romantic loves or interests (or at least a worldview which designates this as possible and desirable to some degree).
As far as jealousy, people experience jealousy in mono relationships all the time. It's a mix of irrational expectation that the relationship should last forever and lack of security in your own skin. This ends up coming out like fear of loss or abandonment (as Mag said). There's lots and lots of information on jealousy out there and so long as you are looking inward for the cause and solution, you'll be fine.