No one could tell what's the possibility, depending on how she deals with problems. If she's an introvert, there is a likelihood that she will suppress her emotions instead and that is akin to a time bomb. Apart from bringing adverse effect, she will one day explode or reach a lowest point.

I suggest she speak to someone in the family/ among her friends whom she can believe in, or someone who can give good advice/ guidance. If this person detects that it's severe, seek professional help. There's nothing like getting a 3rd party intervention to help see things from a new perspective.