In Faithful Feelings, Matthew Elliot offers a clear summary about emotions:
Emotion is always about something; it has an object. Emotion tells us about our values and beliefs. It can also tell us about the beliefs and values of others. Emotions are not necessarily rational, not because they are intrinsically irrational impulses, but because we can be irrational people. Emotions are often a powerful motivation…. Emotions are highly complex phenomena that rely upon both our conscious and unconscious mind, memories, cultural forces, family upbringing, and our personalities. These factors interact and respond to one another in an incredibly complex web of interdependent beliefs and values to produce particular emotions in particular circumstances.
(Justin and Lindsey Holcomb, Rid of My Disgrace, p. 43, 44).