To release someone is more than simply letting them go. The definition of the word "release" means to set people free from confinement or bondage, to deliver or to emancipate. It is a word used to describe the release of an animal from a cage or rescuing a hostage from a hostage taker.
If you say you have released someone from a wrong committed against you the strongest evidence that you have truly set them free will be discovered in your heart where you no longer demand they remain imprisoned in your judgment. That is what it means to release someone. The greater bondage is these situations will always be experienced by the one who holds the key to a persons freedom, but refuses to open the lock.