I have also read through the posts and honestly I cannot advise to either look elsewhere for your happiness or not. I am concerned about the woman! You obviously care for the person for whatever reason and that is refreshing to hear.
It seems to me that the woman has emotional problems and being interested in nutritional psychotherapy I cannot advise, that conventional doctors or psychologists are in a position to help her, except putting her on a long-term medication regime, which is not necessarily going to solve her problems.
I also realize that if she does not WANT treatment, there is little you can do to help her. However, therapy may turn out to be more simple than appears at first sight.
Knowing that most mood disorders are related to Hypoglycemia it may be worthwhile to have her tested with:
If she scores high it may be positive for hypoglycemia, which could be responsible for some of her behvaiour. This can be treated by going on a Hypoglycemic Diet without recourse to drugs. Please discuss with a Nutritional Doctor, Clinical Nutritionist or a Nutritional Psychotherapist, if you want to.
Of course, this all depends on her willingness to recognize that she suffers from some emotional problems.