It is the reaction to an unfortunate event. The time it takes to reduce is not fixed and depends on the amount of tragedy as well as the way a person can absorb it. Generally it does not take more than a couple of weeks for most people to rebound at least to a reasonable extent and a person can feel better.
Being sad when the situation calls for it is not a bad thing as it does show that you have a humane side which is very important. A bit of support from the loved ones is the best tonic to get rid of the feeling.
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Depression is a condition when a person feels sad and there is no particular time frame in which the person will get back to normal. It is a bit of sinking feeling as well as ideas of one being completely helpless. It can be temporary in nature but can also be a permanent condition.
It can be caused by some event or simply because a person suffers from it. It can be instigated by issues that are very small in nature. A person often perceives things in an exaggerated manner. Often a patient needs treatment which is generally in form of counseling.
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