"Forgivness" is a personal thing and not, under any circumstances, a requirement to healing. For some, it's a stepping stone to healing, for other's it's an exercise in futility.
For me, my choice to "forgive" does not mean forgetting or, allowing to continue, the sins that have been committed against me, personally. My willingness to forgive is in recognition of my own humanity - I've committed sins against others over my lifetime, as well, and it behooves me to accept the fact that I'm just as flawed as the next person, regardless of how much damage they might inflict.
By forgiving others, I can (if I so choose) forgive my Self.