There is no diagnosis in the DSM-IV for "bipolar depression". DSM-IV sctn 296 outlines the diagnostic criteria for bipolar disorders, and seperates the difference between types 1 & 2 and NOS. With the most common form of bipolar disorder, type II, you generally have short periods of hypomanic activity followed by long periods of mild to major depression. Bipolar type I still has manic episodes, but the depression cycles are much shorter. NOS includes your rapid cycling (uncommon) and psychotic-biased bipolar. The phrase "manic-depression" is often used to describe bipolar disorder, as it is a symptomatic description, but there is no actual diagnosis for "manic-depressive" in the DSM-IV. Bipolar is called bipolar because you cycle uncontrollably between two extremes of mood conditions - hypomania and depression.

The problem with bipolar disorder is that the diagnostic criteria are so broad that it can encompass a wide variety of problems. Bipolar II, for example, only has 5 diagnostic criteria, and almost all of them are subjective. In much the same way that undisciplined children get diagnosed with ADHD these days, so also do people get themselves labeled as bipolar who simply have behavioral issues. Again, the only way to be sure is to submit to evaluation in a treatment facility, where they will monitor you for a short while and see if you do cycle between uncontrollable and inappropriate mood changes.

I'll say again, I'm not a doctor, but I did attend a "living with bipolar" support group faithfully and I'm full to the gills with bipolar information. The best way to live with and support a bipolar person is to understand their disorder, and so I did what I had to do for my wife. I can't stress it enough though... the only way to effectively deal with a mood disorder is with professional help, and you have to demonstrate that you want the help and are willing to advance your therapy. This person needs to see mental help professionals.