GEN1082 If one has caused anguish to another and has harassed him, embarrassed him, or spoken badly of him, he cannot attain atonement without [first] asking forgiveness from him.  So our Sages, of blessed memory, said Baba Kama 92a: Even though he has monetarily compensated the other for his shame and the suffering inflicted through beating, he is not atoned for these wrongs until he asks his forgiveness, i.e. even after returning Abraham’s wife, Avimelech needed forgiveness.   Abraham’s willingness to pray for Avimelech testifies to his having forgiven him.  (Peirush Mar”d)  GATES 74-5