How would you describe poor/bad family relations?

Solution 1:

The word dysfunctional is often used to describe personal relationships which are unhealthy or toxic. It's so common, the term dysfunctional family has its own Wikipedia page. Relationships can be dysfunctional in many ways, some of the more common being lack of empathy or boundaries, a power imbalance, or constant conflict or arguing.

Solution 2:

A fraught relationship (MW)

causing or characterized by emotional distress or tension : uneasy; "a fraught relationship"