A degree of jealousy can be useful. A lot of it can be toxic and destructive.May 9, 2019, By Sarah DiGiulioAt one time or another, we’ve probably all felt the twinge of the green-eyed monster. Is my boyfriend’s banter with his attractive, known-each-other-since-kindergarten best friend more than that of “just friends”? Does my boss think more of the other junior associate than of me? Why did my best friend invite her to the movies, but not me?Jealousy is the emotion we feel when we feel fearful of losing someone or a relationship that is very important to us, Robin Stern, PhD, associate director for the Yale Center for Emotional Intelligence, tells NBC News BETTER.src: https://www.nbcnews.com/better/lifestyle/what-your-jealous-feelings-are-telling-you-what-you-should-ncna1002411narrated by: Medardo Jr. Magallanes Lazarte