Is it permissible to treat one's cousin in kind and cut ties with him due to his continuous ill-treatment?

Allah has made it obligatory to maintain kinship ties and has warned against severing them. Cousins are among the kin with whom ties must be maintained in a good manner, as long as no religiously prohibited act results from it. If a Muslim fulfills what he has been commanded regarding maintaining ties and good treatment, then he has discharged his duty. It is not permissible to boycott a cousin forever, especially if he is a forbidden degree of kinship (mahram), due to the Prophet's (peace and blessings be upon him) saying: "It is not permissible for a Muslim to abandon his brother for more than three (days)."