I see it all as a set of dyads linked to purpose. The emotion informs you, and in some cases you communicate it to inform others. With this set of simple dyads all human emotions can be recreated by mixing and adjusting intensity of signal . Each dyad deals with the same “info” adjusting towards positive or negative.

The dyads:

Joy and sadness (objective) this is for the stuff you need to chase, joy when you have it, sadness when you don’t. Mmm eating steak makes me joyful.

Anger and fear (obstacles) how to deal with the obstacle between yourself and your joy. Anger, I can overcome. Fear, I should avoid it.

Trust and disgust (inclusion) what should I include or exclude from my environment to maximise the chance of joy.

Anticipation and surprise (awareness) how much do you know about this situation?

That’s it. So, if an emotions is recurrent. Indeed, it’s that its purpose was not put into action. Depression tells you to stop, think and devise a plan to go find joy. Constant disgust tells you something has to be removed from your environment.(or that you should change environment)

Trauma is when this compass gets damaged, especially if trauma was the result of malevolent actions intentionally messing with your emotions to gain control. One recurrent way cults and groups abuse their members is by suppressing anger, disgust and sadness. Those signals shouldn’t exist in the perfect community. The community is not perfect, but the signal has to be muted to enable the make belief.