Joshua Coleman's Book - https://www.amazon.co.uk/Rules-Estrangement-Adult-Children-Conflict/dp/0593136861

As previously noted, there are many path to estrangement. Not all family estrangement is caused by dysfunctional  family dynamics. Some are caused as a result of some new being introduced to the family.

Weekly membership support group 

https://recoveryfromfragmentedfamilies.vipmembervault.com/products/courses/view/1121940 

Private Facebook group.

https://www.facebook.com/groups/587817455514932