Maybe she needs to do something that would make her feel really good about herself...like finishing a marathon (offer to do it with her and be her motivator) or looking for a new job or facing a challege of some sort head on. Or maybe she needs to talk to a therapist if the issue is much deeper, which I feel is the case. Sometimes you can only be an ear for a person. I don't think you can change anything for her. Let her know there is no shame in therapy.
So, so you think you can tell Heaven from Hell,
blue skies from pain.
Can you tell a green field from a cold steel rail?
A smile from a veil?
Do you think you can tell?
And did they get you to trade your heroes for ghosts?
Hot ashes for trees?
Hot air for a cool breeze?
Cold comfort for change?
And did you exchange a walk on part in the war for a lead role in a cage?