James 4:8 says, “Wash your hands, you sinners, and purify your hearts, you double-minded.” Take an honest assessment of your heart and what role you may have had in the demise of a certain relationship.  First John 1:8-9 says, “If we claim to be without sin, we deceive ourselves and the truth is not in us. If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness.” When you confess your sin to God and ask Him for forgiveness, you are able to forgive others and let go of resentment and bitterness you may be harboring within your heart.