The fourth commandment, honour your parents and rightful authority, is based on recognizing rightful authority was given by God. When a parent or a superior or a civil leader is no longer exercising rightful authority, we are no longer obliged to obey or submit to them.
In your case, when a parent is abusive, be it physical, financial, emotional, verbal or worse, that is no longer exercising rightful authority. When a parent fails to acknowledge their role is to assist their children to find their own path but to try to force them into his/her own idea for them in career or marriage, they are not exercising their rightful authority. Parents don’t own their children; they are merely privileged to raise them to know God, to help them pursue freely the God-given truth, goodness and beauty in their lives.
Children who choose to disobey their parents who misuse their authority cannot be said to be breaking the fourth commandment.
However, even with abusive parents, children must still endeavour to respect them, not in sense of permitting or condoning their abusive behaviours, but in exercising genuine filial concern for the well-being of their bodily and spiritual health. Our parents have given us life and have provided for us. For the failures of our parents, we must offer prayer and reparation for their conversion, and sometimes even kind words of truth to help their correction; and in their need, especially in sickness and in their old age, we should come to their aid to ease their difficulties. Who knows it would not be in such a final moment that God would provide the necessary grace of conversion and reconciliation for them and for us?