For me, I find myself jealous more often than I'd like, but it stems from the insecurity of feeling like I'm not good enough for my partner or for myself and am therefore easily replaceable after the front is discovered.
Yes but I don't act on it. I've only experienced it with crushes though, never in a relationship. I don't believe it's about being "good enough", I believe it's pure lottery about the whims of the heart of another person. There's nothing you can do about it. They can pick someone else for whatever reason. Love/infatuation is pretty random.
So jealousy isn't about insecurity, it's simple the fear they will pick someone else. Or in the totally simplified way, it's discomfort from knowing someone else is getting what you want to be getting. And it can be as little as spending time with the person.
No but when I'm into someone I become kinda possessive of them as in expect them to be faithful at least. If they happen to be a player I lose interest pretty quick
Then, you should Know the fact that each being is replaceable since death is a step ahead of life. Yet in the wakeful life, living without the mentioned sin will make each life so much more better.