I have addressed this in a previous related question. The relative who molested me admits to doing it, but makes up excuses and won’t accept responsibility. I know that he knew better even back then, but I accept that he is incapable of carrying the burden of guilt, and so I forgive him for being weak.
The same goes to my mother who remained blissfully ignorant that her kids were miserable and practically suicidal before puberty even hit. As a mother, I know when something is bothering my son… but I forgive her for performing a biological function even though she was incapable of handling the job that follows it, and for also being too weak to handle the guilt of accepting accountability.
That being said, I have nothing to do with my perpetrator. I do deal with my mother, but have progressively backed away and in time plan to cut ties.