Fish Bear,
I suffered from depression as a chronic pain sufferer about 10 years ago. It took three years to beat the funk. My wife stuck with me and I have to say I do not know why. Depression must be treated, somehow you need to get your wife to take the medicine and get help. It is much more then just taking the medicine, at least for me. It requires a complete change, I found solitude in Self Help study and meditation along with the medicine. Keep the faith she really does not want to be that way.