Have one last professional session where she thinks you're all fixed up and normal now. Don't see her for a few months. Then send her a message on Facebook asking her to go on a hike, connecting it in some casual way to some conversation you had in the past. Maybe include a brief thank you for the help she gave you and mention again that you are all healthy and doing great (if you aren't mentally healthy you aren't going to attract her). At that point you are (a) no longer a professional client (b) don't come off as desperate and (c) have a chance to build something slowly with her in another context. But your odds are still low, so keep cultivating relationships with other women and focus on being mentally healthy so that you will attract the right kind of person.