Understanding Jealousy – From Emotion to Mental Illness

Jealousy, a complex emotion, has been with humanity throughout its history, influencing interpersonal relationships, decisions, and even cultural norms. While often perceived as a natural emotion, there’s a spectrum, ranging from healthy emotional responses to pathological manifestations.

Jealousy had evolutionary benefits. In prehistoric times, it served as a mechanism to ensure mate fidelity and protect resources, thereby increasing chances of survival and progeny.

Interestingly, studies have indicated that men and women might experience jealousy differently, largely due to evolutionary pressures. For instance, men historically feared physical infidelity, risking investing resources in someone else’s offspring, while women feared emotional infidelity, potentially resulting in a loss of support.

Types of Jealousy

General Jealousy

General jealousy is a basic emotion that most individuals experience at some point in their lives. It is a reaction to perceived threats to one’s self-worth, position, or relational stability.

What is it and why do we feel it?

Humans are social creatures, and as such, they are conditioned to form bonds and hierarchies. When one perceives a threat to these established structures, jealousy can emerge. For example, a person might feel jealous when a coworker is praised or when a partner spends a lot of time with a new friend. These feelings can serve as both motivational cues, urging individuals to improve or adapt, and as protective mechanisms, signaling potential problems in close relationships.

Why it’s normal: It’s an inherent part of our emotional spectrum. Occasional bouts of jealousy can even be constructive, prompting self-reflection or motivating personal growth.

Morbid Jealousy

Definition: Morbid jealousy, often called Othello syndrome, is where an individual believes, without any substantial evidence, that their partner is being unfaithful. This belief persists even when confronted with contrary evidence.


  • A husband constantly checks his wife’s phone for unknown numbers.
  • A wife accuses her husband of infidelity every time he’s late without clear reasoning.

How it differs from general jealousy:

While general jealousy might emerge from real events or stimuli, morbid jealousy tends to be based on imagined scenarios, misinterpretations, or even delusions. It’s more persistent and can lead to extreme behaviors, such as stalking, interrogating the partner incessantly, or even violence.

Obsessive Jealousy

Definition: This is a more intense form of jealousy where individuals find it hard to shift their focus away from their obsessive thoughts, even when they cognitively understand their irrationality.


  • Constant rumination about the object of jealousy.
  • Inability to control intrusive thoughts.
  • Engaging in repetitive behaviors like checking a partner’s phone or social media.


  • A boyfriend repeatedly asks his partner about a past relationship to the point of distress.
  • A girlfriend spends hours every day stalking her partner’s ex on social media.

Obsessive jealousy can often be linked to deep-seated insecurities, traumatic past experiences, or underlying mental health disorders like obsessive-compulsive disorder.

Jealousy as a Mental Illness

Clinical Definition: When jealousy inhibits daily functioning, causing irrational decisions, aggression, or self-harm, it surpasses normal emotional reactions and enters the realm of mental health disorders.


  • Persistent and intrusive thoughts.
  • Aggressive behavior based on jealous beliefs.
  • Social withdrawal due to constant suspicions.


Diagnosis is generally made when the behavior and feelings are out of proportion to the triggering event, or when there’s no real event triggering the feelings at all. The persistence and intensity of feelings, coupled with the negative impact on daily life, are key diagnostic indicators. Each type of jealousy, while rooted in the same basic emotion, presents uniquely and has different implications for the individual and their relationships. Recognizing and understanding these differences is crucial for effective management and intervention.