Hi. I am a college student and am worried about my friend who I think may be depressed. She spends a lot of her time in bed, skips classes, and sometimes goes a couple of days without eating real meals. Other times, however, she seems happy and outgoing, but then occasionally brings up topics that are causing her stress and says her life is depressing. I am confused as to whether or not she has a serious problem, or is just going through bouts of sadness like everyone else does.