There is a great deal of confusion between feelings and mood states. Feelings (or emotions) are normal, healthy aspects of being human. Sadness, anger, joy, and fear are all common feelings that every human experiences, often daily. Mood states are not feelings. Depression, anxiety, and Bipolar Disorder (often known as manic depression) are mood states and can be considered mental disorders when severe enough. This isn't necessarily the case, as most people have experienced some type of depression or anxiety in their life time without it being serious enough to constitute a mental illness. We can say that we "feel depressed" or "feel anxious," which adds to the confusion between feelings and mood states.
Mood states may be understood as defense mechanisms that serve to protect us from underlying feelings. For instance, if we experience our anger as unacceptable or threatening, we might "depress" it and end up being "numb," resulting in not being in touch with the underlying anger. People who suffer from depression often describe themselves as being lethargic, fatigued, hopeless, or despairing. We cannot be in touch with our emotions when we are depressed. Reversely, when we are in touch with our feelings, we are not depressed at that moment. Anxiety may also be a way to manage underlying emotions. If our anger becomes too intense, we might react by becoming highly anxious. In this case, the anxiety is in response to a perceived threat induced by our anger. To complicate this further, if our anxiety then becomes too intense, we might then clamp down on it and become depressed. I describe this to my patients as layers upon layers, with the root feeling (which is pure and healthy) being buried deep down. So in this example, anger is the pure, healthy emotion that the individual has come to believe is bad, dangerous, or unacceptable. So Anger -> Anxiety -> Depression. Freud described depression as "anger turned inward." I believe this is what he meant by that explanation. Thus, a person might only experience his depression or anxiety, having suppressed his anger to a point where it cannot be easily accessed. But if a person suppresses one emotion, he suppresses all emotions. So when a person is suffering from depression, he cannot fully inhabit his anger, joy, fear, or sadness.
In psychotherapy I help my patients explore what feelings they might be defending against by employing the defenses of depression or anxiety. By teaching people that their feelings are normal and healthy and not to be feared, they start to shift their relationships to their emotions. Over time, this helps people learn alternate ways to manage their feelings so that they no longer believe they have to push their feelings away at all costs. We may view depression and anxiety disorders as forms of "acting in," i.e. turning inward to try to manage difficult emotions. In my next blog post, I will address "acting out" behaviors that people may employ as alternate ways to attempt to manage internal emotional states.