in my therapy we address the trigger of abandonment and attachment fears not by any set routine or method but by working with current day triggers (noticing being triggered, calming the neurological response with grounding skills etc) and developing an understanding of where those fears first came from. Over time,, by recognizing the present state of having those things triggered and putting them together with the understanding of where those responses and fears originated, it becomes easier to calm myself down when they get triggered. For me its just about recognizing where those fears originated and separating them from present day issues. When they get triggered up I remind myself the intensity of those feelings comes from past stuff that is not applicable to current day circumstances. Over time it gets easier to remind myself of that.