Diane is the only child of two professional parents. She did well in high school and had several close friends. However, her grades suffered when she got to college, and she spent one semester on probation before she graduated. She met Don while in college, the two married soon after graduation, and had two children. Diane and Don decided that Diane would stay home until the children were in school, because Don's job with a prestigious accounting firm enabled him to support the family. Three months ago, however, Don came home from work and announced that he was having an affair with another woman. He had decided to leave Diane. The divorce proceeded quickly, and although Diane retained custody of the children, she had to move into a small apartment. She began to look for work, and eventually took a job that she disliked. Diane often finds herself thinking about how quickly her life has changed! She has been sad for the last few months, and sometimes lies in bed crying after the children are asleep. She also eats a lot more than she used to and sometimes has difficulty getting to sleep at night.

What is his possible mental disorder? Explain. What is a possible treatment?