Jealousy
Envy

As emotions go, jealousy is neither subtle nor kind, but it is definitely complex, encompassing feelings from fear of abandonment to rage to humiliation. It strikes both men and women when they perceive a third-party threat to a valued relationship, and that distinguishes it from envy, which involves wanting something someone else has. Conventional wisdom holds that jealousy is a necessary emotion because it preserves social bonds, but it more often destroys them. And it can give rise to relationship violence.