This is an area where I think we disagree. I have a strong probabilistic belief that putting resources into relationships that do not serve me well is not rational, as doing so does not serve my goals for relationships. Let me be clear that this intentional managing of relationships applies to an individual as such, not relationships to a group. Cultism to me, by contrast, implies a strong and charismatic group leader telling those who joined her/his group to cut off relationships with others who did not join that group. So maybe a difference between how we see the world here.