Social support is among the strongest modifiable predictors of outcome after trauma. One person, not a network — the bar has to be reachable from where you are standing.
That is the whole task today.
Tell them something small first, and see how they hold it.
Not all of it, and not on anyone's timetable but your own.
Peer groups, warmlines and communities count. So, eventually, does the relationship you build with yourself.
How strong is the evidence? Brewin, Andrews & Valentine, meta-analysis of risk factors for PTSD, 2000.