L.B.
Depression is caused by an abnormality of chemicals in the brain. It is not caused by a feeling. For example, two people could have the same feeling, one person will become depressed (that person has an inbalance of the chemicals in their brain) the other person will not become depressed and will beable to cope with the feeling because their brain chemicals are in balance (norepinephrine and serotonin).
An inbalance in brain chemistry is what makes the person unable to cope with life, a feeling, a situation or just not able to cope, everything feels hopeess even minor incidents. everything feels difficult, So yes, someone can be depressed just because they feel depressed.
Someone who is depressed can have intermittent feelings of happiness or laughter, but even with this temporary feeling of enjoyment they are still depressed they still have feelings of hopelessness and despair even though they may laugh at a joke or appear happy.
Someone who is not depressed can have intermittent feelings of sadness or the blues, feeling sad once in a while is not the same thing as depression. Someone may feel sad for a day or two about an unfortunate situation but beable to cope and get over the feelings of sadness in a relative short time.
Someone who is depresed cannot "snap out of it" due to the chemical inbalance in their brain they perceive things in a faulty way and have trouble seeing things in a realistic manner.
There are different types of depression: For example;
dysthymia is a chronic feeling of sadness, just sadness that does not go away, unhappy but not deep dark despair, someone feeling this way should see the MD
clinical depression is a deep dark place that often needs psychiatric care,