Is the failure to maintain ties with kin who are abusive towards parents considered a severance of kinship ties, and does sin result from that?

Maintaining kinship ties is obligatory, and severing them is forbidden and a major sin. It is not permissible to abandon kinship ties because of their harm to parents, nor is it permissible to obey parents if they command to sever them. Efforts must be made to reconcile disputants, and supplications should be increased for success in reconciliation and reunification. Kinship ties must be maintained in any possible way, such as visiting and giving gifts to those who are able, or helping with tasks, or communicating in writing with those who are absent. If one is unable to visit or fears harm, then they should maintain ties in whatever way they can. The lowest degree of maintaining ties is avoiding abandonment, and maintaining kinship ties through speech, such as greetings. Custom has a bearing on defining what constitutes maintaining ties or severing them.