You can’t tell someone out of their fear.
What you can do, if they are scared, is be there for them.
In whatever capacity they need you to be.
For some, that’s simply to be silent.
For others, it’s a hug, or a thoughtful response.
Or, they might need you to walk with them, through the door.
Perhaps paint a different picture, of what might be possible.
Whatever the specific case, it’s about making a deeper connection, not giving instruction (which is closer to disconnection).
People need to feel afraid, for their own reasons. Don’t try to take that away from them.
Instead, give them something new that they can take with them as they move forward.