LW2 could try saying to each of her problem co-workers, "You know what? I like you, and I like her too. What I DON'T like is hearing the two of you criticize each other."

LW1 has lived with her husband about 5 YEARS with his deteriorating mental health and has done NOTHING before writing to Margo? Something else is wrong with this picture if it takes a wife 5 years to say the man needs help. One marries for better, for worse, in sickness and in health. If the man had a wound that wouldn't heal, she surely would not have let him go without dragging him to a doctor, surely?

I would suggest getting closest family and friends together and having an intervention, telling him that they know he's in pain and distress, and pressing him to keep an appointment that the wife has made. If she walks out after 5 years of this worsening state, he could commit suicide.