Clinical depression (Major Depressive Disorder) is a serious medical illness that negatively affects how you feel, think, and act, caused by a complex combination of genetic, biological, environmental, and psychological factors. Key emotional symptoms include a persistent sad or "empty" mood, loss of interest in activities, and feelings of hopelessness, while physical symptoms can be changes in appetite or sleep, constant fatigue, and unexplained aches. Evidence-based treatments include psychotherapy (such as Cognitive Behavioral Therapy) and antidepressant medication (like SSRIs), sometimes combined with procedures like TMS for treatment-resistant cases. It is crucial to seek a Psychiatrist for medication management and a Licensed Therapist (Psychologist, LCSW) for therapy; look for reputable mental health clinics or hospitals with a dedicated psychiatry department. The cost can vary widely, with therapy sessions ranging from $100-$250 and generic medications from $10-$50 per month. The most important guidance for support is to listen without judgment, encourage them to seek and continue professional help, offer practical help with daily tasks, and reassure them that they are not alone in their struggle.