What is the ruling on expelling a relative who wronged my mother in her youth and caused her a psychological illness, knowing that she is unable to expel him or confront him?

One should be characterized by patience, forgiveness, suppressing anger, and maintaining ties of kinship, for severing kinship ties is a major sin. The one who truly maintains ties is not he who reciprocates, but rather he who connects with his kin even if they sever ties with him, and who treats them kindly even if they treat him poorly, and who gives to them even if they withhold from him. Allah has promised those who forgive an increase in honor and has promised them forgiveness. The fundamental aspect of the Prophet's (peace be upon him) character is that he does not repel evil with evil; rather, he pardons and overlooks. Yusuf (peace be upon him) forgave his brothers despite their great harm, so the harm from this relative will not be like the harm from Yusuf's brothers. The solution lies in fearing Allah, maintaining ties of kinship, and doing good, for Allah does not waste the reward of those who do good, and this results in the expansion of hearts and the tranquility of souls in this world, and Allah's forgiveness and mercy in the Hereafter.