Paying for Other People's Sins

One of the most tragic but common phenomenons is the reality that we often pay for someone else's sins. What do I mean by this? If we have been mistreated or abused by someone in our past, and we have not forgiven that person, and the emotional/spiritual wound has not been healed, then we are likely to over react. To use a physical illustration, if we suffer a severe burn on our arm and it is not treated nor bandaged, then the slightest contact will cause it to hurt, and we may scream as a result. If we do have the burn treated and bandaged then the same slight contact will not have the same effect. When people respond in a disproportionate way to something that has happened, I believe that oftentimes unhealed/forgiven wounds are the cause.
How do we avoid this? Proverbs indicates that we can choose to take, or not to take offense. "The vexation of a fool is known at once, but the prudent ignores an insult." (12:16) "Good sense makes one slow to anger, and it is to his glory to overlook an offense." (Prov. 19:11 ESV) Jesus exemplifies this on the cross when He says, "Father, forgive them, for they know not what they do." (Luke 23:24 ESV)
Sometimes the offense is so great that we are overwhelmed. Then we must call out to God for His power to forgive. Cry out for His compassion and receive His love for us personally. If we don't then we end up punishing person B for person A's sins.