It’s important to let go and forgive. Here are some reasons why.
Forgiveness is good for your heart—literally. One study from the Journal of Behavioral Medicine found forgiveness to be associated with lower heart rate and blood pressure as well as stress relief. This can bring long-term health benefits to your heart and overall health.
A later study found forgiveness to be positively associated with five measures of health: physical symptoms, medications used, sleep quality, fatigue, and somatic complaints. It seems that the reduction in negative affect (depressive symptoms), strengthened spirituality, conflict management and stress relief one finds through forgiveness all have a significant impact on overall health.
A third study, published in the Personality and Social Psychology Bulletin, found that forgiveness not only restores positive thoughts, feelings and behaviors toward the offending party (in other words, forgiveness restores the relationship to its previous positive state), but the benefits of forgiveness spill over to positive behaviors toward others outside of the relationship. Forgiveness is associated with more volunteerism, donating to charity, and other altruistic behaviors. (And the converse is true of non-forgiveness.) https://www.verywellmind.com/the-benefits-of-forgiveness-3144954