Generally, we shouldn't ignore our emotions, but we also shouldn't act on them without reflection. Emotions are signals, sometimes unreliable, but they correlate with something.

This may be a selective memory bias, but my experience is that when I was jealous, there usually was a reason.

(However, I don't want to generalize from one mind. Maybe I am better calibrated than average. Maybe I only receive exceptionally strong signals, where the probability of some real cause is much bigger. There were situations where jealousy didn't warn me. Someone else might be more sensitive to weaker signals, and therefore also have more false alarms.)