Siding with one set of clients over the other on the merits of the cases before them  is what judges are supposed to do in civil courts.

The problem in many, but perhaps not all, family courts, is that the judges tow the line on the 'pay the instigator' protocol that serves the lawyers, and ultimately only the lawyers.  Those family court judges use the power of the state to administer a private shake-down operation benefiting lawyers at the expense of broken families.  

Like you, they say the clients are to blame, but their conduct is repeated and, with the benefit of the pay-the-instigator formula to provide guidance, predictable.  In these situations, one cannot go far wrong by following the money ... straight into the lawyers pockets.