Depression....

Depression can be recognized as sadness or despair.  We all go through it.  However, we need to look into the problem if it is causing problems with your memory, higher thinking and completing tasks. It can also include the feelings of sadness, hopelessness, and despair.  It can also affect your immune system.  All of these things can interrupt your ability to think clearly, which also impacts your memory and decision making skills.  You could have problems with seeing your way through these issues.  All of these thinking problems can lead to alcoholism and suicide.  This is all related to a reduction and interruption of the brains chemical messengers.
Some of the things that you can learn to do are to break down the tasks into smaller pieces.  Learn to recognize and improve your brain function.  Be aware of the thinking that leads you into a pit of ugliness.  Do not fight to or it will just get bigger.  Learn to be the center where all of this thinking is released. 
There is nothing good or bad, thinking makes it so.  Shakespeare

Try LENS neurofeedback, it helps to keep the feather of depression in the distance so that you can function better, and blow it away.