The conventional read on someone who has detached from their family is that they've gone cold. The distance is the tell. The actual sign is quieter: a holiday passes without trying to repair the silence.
Real disengagement is harder to spot because there's no signal being sent. The person isn't punishing anyone. They've stopped expecting the family to behave differently.
Stopping that work is harder than going no-contact. Letting the holiday pass without trying to fix the silence is a surrender of a job you were given before you could refuse it.
The calm isn't indifference. It's the absence of urgency. The person has finally agreed with reality instead of arguing with it.
The grief is real. The first holiday without performing is rarely peaceful. But the work isn't in cutting people off-it's in noticing the moment your hand reaches for the phone and asking what you're trying to prevent.