There seems to be a great deal of variation in how much jealousy a person feels — for some it’s an ugly, painful struggle but for others it is something rarely felt if at all.
One recurring trigger for jealousy that came up many times in discussion is when a lover feels “out of the loop” — that is they don’t feel like their other lover(s) have communicated openly about their feelings, activities, or intentions involving a third-party. Sometimes it occurs when a person or event reminds one of a past loss, or suggests an impending breakup or problem. Jealousy might be caused by feeling neglected or abandoned.