His family are not responsible for him. He's a grown man, responsible for himself.
It looks like he's felt completely capable of making it back alone, otherwise he wouldn't have set out. Adults don't need their hands held. It looks like he's taken a wrong turning en route, there was no bus when they all expected there to be one, and he's made his decisions alone.
We've all taken wrong turnings in life that have led us down paths we neither wanted nor expected.
There's no need for blame, guilt, or shame, on anyone's part.