If this situation becomes intolerable, you may have to confront the student directly. Express your concern that he or she does not appear to be interested in improving their course grade and that further tutoring efforts may be a waste of time and money. This may be enough to snap some students out of themselves and return to the task at hand. Others may just need a little more interactivity added to the tutoring sessions, or some variety in the routine. If I don't pass this class, I won't ever succeed at college.
Some older students present even more grade anxiety than an incoming traditional freshman.
They have returned to college after a failed career choice or a failed marriage or a difficult life in general. Making matters worse, their scholarship or other financial aid assistance is directly connected to performance. Too many failed classes, and all hopes for a college degree are gone. This is the mindset you may be dealing with as a tutor. An overanxious student is a barely-functioning student.