Depression or mood swings also are common in women with PCOS. Although more research is needed to find out about this link, there are studies linking depression to diabetes. Therefore, in PCOS, depression may be related to insulin resistance. It also could be a result of the hormonal imbalances and the cosmetic symptoms of the condition. Acne, hair loss, and other symptoms of PCOS can lead to poor self-esteem. Infertility and miscarriages also can be very stressful. Medications that restore the balance to hormone levels or antidepressants can help these feelings.
http://www.diabetes.org/type-1-diabetes/PCOS.jsp
In PCOS, depression may be related to insulin resistance 
