You may experience jealousy or panic about your partner potentially being with someone else.

Common emotional reactions on Relationship Breakups:

Nearly everyone experiences the pain of a breakup of an important love relationship at some point in life.

Many people are forced to cope for the first time with the breakup of a significant relationship during their college years.  It is difficult to know just how painful a relationship breakup can be until it happens in one’s own life.  Intense feelings of sadness and despair are a common reaction to the end of a relationship.  Psychological research shows that the emotional response to the breakup of a romantic relationship strongly resembles reactions to what would appear to be more traumatic losses, such as the death of a loved one or the diagnosis of a life-threatening illness. 

The following are common emotional reactions to the loss of a romantic relationship: 

• Denial – It may be very difficult to believe and accept that the relationship is ending.  It is painful to experience a loved and trusted partner seeming to care so little about the relationship and your feelings. 
• Grief and Despair – It is normal to feel sad and lonely, and to cry a lot. You may feel an intense need at times to make contact with your ex-partner.  Particular times during the day, such as waking up in the morning, may be especially difficult.
• Fear – It may be frightening and difficult to imagine life without the significant other.  You may fear that you will never find love or feel happy again.
• Anger – Anger with a partner who has caused pain by initiating or contributing to the breakup is a common emotional response.
• Self-blame and Guilt – You may obsess over what you could have done to cause the breakup, and may attempt to “bargain” with an ex-partner to give the relationship another chance.    If you initiated the breakup, you may feel guilty about causing pain to your partner.
• Jealousy – You may experience jealousy or panic about your partner potentially being with someone else.
• Confusion – Life may feel strange or incomplete without your significant other.  You may question who you are, and the meaning of life without your partner.
• Relief – You may feel some sense of relief from negative feelings associated with the relationship that resulted from fighting, insecurity, or boredom.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            (Link- https://www1.villanova.edu/villanova/studentlife/counselingcenter/infosheets/breakup.html)