"How long is this going to take?"
It is a fair question.
It is also the wrong first question.
Trust does not rebuild because six months passed.
Time gives behaviour a chance to become evidence.
If the behaviour is still unreliable, time simply produces a longer period of mistrust.
There is no universal deadline
One person may feel significantly safer after several months.
Another may need much longer.
The timeline changes with the size of the betrayal.