I have bipolar depression and for the past few years (they are adding up), it has taken over my life.  When I was in the middle of a very serious depression person after person rejected me.  I have found that most people simply do not believe that depression is a real illness.  It is!  Before I Became so seriously depressed, I kept all my problems to myself for years but it got to the point where I could not anymore.  My experience of reaching out did not work out and people, by in large, were not very nice.  I do not know how good of a friend you are to this person but to him/her what he/she is saying is real to them.  It can become very difficult for you, as a friend, to hang in there but if you care about this person, I urge you to try.  Read as much as you are willing to about this illness and you may get some understanding.  If your friend is not taking his/her meds urge her/him to and if they are not working urge her to go to a GOOD doctor and work on getting on a medication that will work.  It is my opinion that good medication and the support of a good counselor and good family and friends helps people who suffer from mental illness.  I hope this helps and thank you for being such a caring friend that you would write in to ask the question.........Pam